* buildscripts/mf-to-table.py (write_fontlist): Improve formatting

[lilypond.git] / Documentation / user / notation.itely

@c -*- coding: latin-1; mode: texinfo; -*-
@c This file is part of lilypond.tely

@c A menu is needed before every deeper *section nesting of @node's; run
@c     M-x texinfo-all-menus-update
@c to automatically fill in these menus before saving changes

@node Notation manual
@chapter Notation manual

This chapter describes all the different types of notation supported
by LilyPond.  It is intended as a reference for users that are already
somewhat familiar with LilyPond.

@menu
* Note entry::                  
* Easier music entry::          
* Staff notation::              
* Polyphony::                   
* Beaming::                     
* Accidentals::                 
* Expressive marks::            
* Repeats::                     
* Rhythmic music::              
* Piano music::                 
* Vocal music::                 
* Other instrument specific notation::  
* Tablatures::                  
* Popular music::               
* Orchestral music::            
* Ancient notation::            
* Contemporary notation::       
* Educational use::             
@end menu

@c FIXME: Note entry vs Music entry at top level menu is confusing.

@node Note entry
@section Note entry
@cindex Note entry

This section is about basic notation elements notes, rests and
related constructs, such as stems, tuplets and ties.

@menu
* Notes::                       
* Pitches::                     
* Chromatic alterations::       
* Micro tones::                 
* Chords::                      
* Rests::                       
* Skips::                       
* Durations::                   
* Augmentation dots::           
* Scaling durations::           
* Stems::                       
* Ties::                        
* Tuplets::                     
@end menu


@node Notes
@subsection Notes


A note is printed by specifying its pitch and then its duration,

@lilypond[quote,verbatim,raggedright]
{ cis'4 d'8 e'16 c'16 }
@end lilypond


@node Pitches
@subsection Pitches

@cindex Pitch names
@cindex Note specification
@cindex pitches
@cindex entering notes

The most common syntax for pitch entry is used for standard notes and
@code{\chordmode} modes.  In these modes, pitches may be designated by
names.  The notes are specified by the letters @code{a} through
@code{g}.  The octave is formed with notes ranging from @code{c}
to @code{b}.  The pitch @code{c} is an octave below middle C and the
letters span the octave above that C

@lilypond[quote,fragment,verbatim]
\clef bass
a,4 b, c d e f g a b c' d' e' \clef treble f' g' a' b' c''
@end lilypond

@cindex note names, Dutch

A sharp is formed by adding @code{-is} to the end of a pitch name and
a flat is formed by adding @code{-es}.  Double sharps and double flats
are obtained by adding @code{-isis} or @code{-eses}.  These
names are the Dutch note names.  In Dutch, @code{aes} is contracted to
@code{as}, but both forms are accepted.  Similarly, both
@code{es} and @code{ees} are accepted

@lilypond[fragment,quote,raggedright,verbatim,relative=2]
ceses4
ces
c
cis 
cisis
@end lilypond

There are predefined sets of note names for various other languages.
To use them,  include the language specific init file.  For
example: @code{\include "english.ly"}.  The available language files
and the note names they define are

@anchor{note name}
@anchor{note names}
@example 
                        Note Names               sharp       flat
nederlands.ly  c   d   e   f   g   a   bes b   -is         -es
english.ly     c   d   e   f   g   a   bf  b   -s/-sharp   -f/-flat
                                               -x (double)
deutsch.ly     c   d   e   f   g   a   b   h   -is         -es
norsk.ly       c   d   e   f   g   a   b   h   -iss/-is    -ess/-es
svenska.ly     c   d   e   f   g   a   b   h   -iss        -ess
italiano.ly    do  re  mi  fa  sol la  sib si  -d          -b
catalan.ly     do  re  mi  fa  sol la  sib si  -d/-s       -b 
espanol.ly     do  re  mi  fa  sol la  sib si  -s          -b 

@end example 

@cindex @code{'}
@cindex @code{,}



The optional octave specification takes the form of a series of
single quote (`@code{'}') characters or a series of comma
(`@code{,}') characters.  Each @code{'} raises the pitch by one
octave; each @code{,} lowers the pitch by an octave

@lilypond[quote,raggedright,fragment,verbatim]
c' c'' es' g' as' gisis' ais'
@end lilypond

@c FIXME: we need this info (hide/unhide) somewhere in the manual, but this ain't the place.  -gp
@refcommands
Notes can be hidden and unhidden with the following commands

@cindex @code{\hideNotes}
@code{\hideNotes}, 
@cindex @code{\unHideNotes}
@code{\unHideNotes}.


@seealso

Program reference: @internalsref{NoteEvent}, and @internalsref{NoteHead}.



@node Chromatic alterations
@subsection Chromatic alterations

Normally accidentals are printed automatically, but you may also
print them manually.  A reminder accidental
@cindex reminder accidental
@cindex @code{?}
can be forced by adding an exclamation mark @code{!}
after the pitch.  A cautionary accidental
@cindex cautionary accidental
@cindex parenthesized accidental
(i.e. an accidental within parentheses) can be obtained by adding the
question mark `@code{?}' after the pitch.

@lilypond[quote,raggedright,fragment,verbatim]
cis' cis' cis'! cis'?
@end lilypond


@seealso

The automatic production of accidentals can be tuned in many
ways.  For more information, refer to @ref{Automatic accidentals}.



@node Micro tones
@subsection Micro tones

Half-flats and half-sharps are formed by adding @code{-eh} and
@code{-ih}; the following is a series of Cs with increasing pitches

@cindex quarter tones
@cindex semi-flats, semi-sharps

@lilypond[verbatim,raggedright,quote,relative=2,fragment]
{ ceseh ceh cih cisih }
@end lilypond

Micro tones are also exported to the MIDI file 


@refbugs

There are no generally accepted standards for denoting three quarter
flats, so LilyPond's symbol does not conform to any standard.

@node Chords
@subsection Chords

A chord is formed by a enclosing a set of pitches in @code{<} and
@code{>}.  A chord may be followed by a duration, and a set of
articulations, just like simple notes

@lilypond[verbatim,raggedright,fragment,quote,relative=1]
<c e g>4 <c>8
@end lilypond

@node Rests
@subsection Rests
@cindex Rests


@cindex @code{\rest}
@cindex @code{r}

Rests are entered like notes, with the note name @code{r}

@lilypond[fragment,quote,raggedright,verbatim]
r1 r2 r4 r8
@end lilypond

Whole bar rests, centered in middle of the bar,
must be done with multi-measure rests.  They are discussed in
@ref{Multi measure rests}.


A rest's vertical position may be explicitly specified by entering a
note with the @code{\rest} keyword appended, the rest will be placed at
the note's place.  This makes manual formatting in polyphonic music
easier.  Automatic rest collision formatting will leave these rests
alone

@lilypond[fragment,quote,raggedright,verbatim]
a'4\rest d'4\rest
@end lilypond

@seealso

Program reference: @internalsref{RestEvent}, and @internalsref{Rest}.


@c FIXME: naming.
@node Skips
@subsection Skips
@cindex Skip
@cindex Invisible rest
@cindex Space note

@cindex @code{\skip}
@cindex @code{s}
An invisible rest (also called a `skip') can be entered like a note
with note name `@code{s}' or with @code{\skip @var{duration}}

@lilypond[fragment,quote,raggedright,verbatim,relative=2]
a4 a4 s4 a4 \skip 1 a4
@end lilypond

The @code{s} syntax is only available in note mode and chord mode.  In
other situations, for example, when entering lyrics, you should use
the @code{\skip} command

@lilypond[quote,raggedright,verbatim]
<<
  \relative { a'2 a1 }
  \new Lyrics \lyricmode { \skip 2 bla1 }
>>
@end lilypond

The skip command is merely an empty musical placeholder.  It does not
produce any output, not even transparent output.

The @code{s} skip command does create @internalsref{Staff} and
@internalsref{Voice} when necessary, similar to note and rest
commands.  For example, the following results in an empty staff.

@lilypond[quote,raggedright,verbatim]
{ s4 } 
@end lilypond

The fragment @code{@{ \skip 4 @} } would produce an empty page.

@seealso

Program reference: @internalsref{SkipEvent}, @internalsref{SkipMusic}.



@node Durations
@subsection Durations


@cindex duration
@cindex @code{\longa}
@cindex @code{\breve}
@cindex @code{\maxima}


In Note, Chord, and Lyrics mode, durations are designated by numbers and
dots: durations are entered as their reciprocal values.  For example, a
quarter note is entered using a @code{4} (since it is a 1/4 note), while
a half note is entered using a @code{2} (since it is a 1/2 note).  For
notes longer than a whole you must use the variables @code{\longa} and
@code{\breve}

@example 
c'\breve  
c'1 c'2 c'4 c'8 c'16 c'32 c'64 c'64
r\longa r\breve  
r1 r2 r4 r8 r16 r32 r64 r64 
@end example 

@lilypond[quote]
\score {
 \relative c'' {
    a\breve*1/2  \autoBeamOff
    a1 a2 a4 a8 a16 a32 a64 a64 
   \bar "empty"
   \break
    r\longa*1/4 r\breve  *1/2
    r1 r2 r4 r8 r16 r32 r64 r64 
  }
  \layout {
    raggedright = ##t
    \context {
      \Staff
        \remove "Clef_engraver"
        \override StaffSymbol #'transparent = ##t 
        \override TimeSignature #'transparent = ##t
        \override BarLine #'transparent = ##t
        \consists "Pitch_squash_engraver"
    }
  }
}
@end lilypond

If the duration is omitted then it is set to the previously entered
duration.  The default for the first note is a quarter note.

@lilypond[quote,raggedright,verbatim,fragment]
{ a a a2 a a4 a a1 a } 
@end lilypond



@node Augmentation dots
@subsection Augmentation dots

@cindex @code{.}
To obtain dotted note lenghts, simply add a dot (`@code{.}') to
the number.  Double-dotted notes are produced in a similar way.

@lilypond[quote,raggedright,fragment,verbatim]
a'4 b' c''4. b'8 a'4. b'4.. c''8.
@end lilypond

@refcommands

Dots are normally moved up to avoid staff lines, except in polyphonic
situations.  The following commands may be used to force a particular
direction manually

@cindex @code{\dotsUp}
@code{\dotsUp}, 
@cindex @code{\dotsDown}
@code{\dotsDown}, 
@cindex @code{\dotsNeutral}
@code{\dotsNeutral}.

@seealso

Program reference: @internalsref{Dots}, and @internalsref{DotColumn}. 

@node Scaling durations
@subsection Scaling durations

You can alter the length of duration by a fraction @var{N/M}
appending `@code{*}@var{N/M}' (or `@code{*}@var{N}' if @var{M=1}).  This
will not affect the appearance of the notes or rests produced.

In the following example, the first three notes take up exactly two
beats, but no triplet bracket is printed.
@lilypond[quote,raggedright,fragment,relative=2,verbatim]
\time 2/4
a4*2/3 gis4*2/3 a4*2/3
a4 a4 a4*2
b16*4 c4
@end lilypond


@seealso

This manual: @ref{Tuplets}


@c  TODO: I'm not certain that Stems belong here in the manual.  -gp
@node Stems
@subsection Stems

Whenever a note is found, a @internalsref{Stem} object is created
automatically.  For whole notes and rests, they are also created but
made invisible.

@refcommands

@cindex @code{\stemUp}
@code{\stemUp}, 
@cindex @code{\stemDown}
@code{\stemDown}, 
@cindex @code{\stemNeutral}
@code{\stemNeutral}. 


@node Ties
@subsection Ties

@cindex Tie
@cindex ties
@cindex @code{~}

A tie connects two adjacent note heads of the same pitch.  The tie in
effect extends the length of a note.  Ties should not be confused with
slurs, which indicate articulation, or phrasing slurs, which indicate
musical phrasing.  A tie is entered using the tilde symbol `@code{~}'

@lilypond[quote,raggedright,fragment,verbatim]
e' ~ e' <c' e' g'> ~ <c' e' g'>
@end lilypond

When a tie is applied to a chord, all note heads whose pitches match
are connected.  When no note heads match, no ties will be created.

A tie is just a way of extending a note duration, similar to the
augmentation dot.  The following example shows two ways of notating
exactly the same concept
@c
@lilypond[quote,fragment,raggedright]
\time 3/4 c'2. c'2 ~ c'4
@end lilypond

@noindent
Ties are used either when the note crosses a bar line, or when dots
cannot be used to denote the rhythm.  When using ties, larger note
values should be aligned to subdivisions of the measure, eg.

@lilypond[fragment,quote,raggedright]
\relative {
  r8 c8 ~ c2 r4 | r8^"not" c2 ~ c8 r4  
}
@end lilypond

If you need to tie a lot of notes over bars, it may be easier to use
automatic note splitting (see @ref{Automatic note splitting}).  This
mechanism automatically splits long notes, and ties them across bar
lines.

@refcommands


@cindex @code{\tieUp}
@code{\tieUp}, 
@cindex @code{\tieDown}
@code{\tieDown}, 
@cindex @code{\tieNeutral}
@code{\tieNeutral}, 
@cindex @code{\tieDotted}
@code{\tieDotted}, 
@cindex @code{\tieSolid}
@code{\tieSolid}.

@seealso 

In this manual: @ref{Automatic note splitting}.

Program reference: @internalsref{TieEvent}, @internalsref{Tie}.

@refbugs


Switching staves when a tie is active will not produce a slanted tie.

Formatting of ties is a difficult subject.  The results are often not
optimal. 

@node Tuplets
@subsection Tuplets

@cindex tuplets
@cindex triplets
@cindex @code{\times}

Tuplets are made out of a music expression by multiplying all durations
with a fraction

@cindex @code{\times}
@example
\times @var{fraction} @var{musicexpr}
@end example

@noindent
The duration of @var{musicexpr} will be multiplied by the fraction.
The fraction's denominator will be printed over the notes, optionally
with a bracket.  The most common tuplet is the triplet in which 3
notes have the length of 2, so the notes are 2/3 of their written
length

@lilypond[quote,raggedright,fragment,verbatim]
g'4 \times 2/3 {c'4 c' c'} d'4 d'4
@end lilypond

The property @code{tupletSpannerDuration} specifies how long each
bracket should last.  With this, you can make lots of tuplets while
typing @code{\times} only once, thus saving lots of typing.  In the next
example, there are two triplets shown, while @code{\times} was only
used once

@lilypond[quote,fragment,relative=1,raggedright,verbatim]
\set tupletSpannerDuration = #(ly:make-moment 1 4)
\times 2/3 { c'8 c c c c c }
@end lilypond

The format of the number is determined by the property
@code{tupletNumberFormatFunction}.  The default prints only the
denominator, but if it is set to the Scheme function
@code{fraction-tuplet-formatter}, @var{num}:@var{den} will be printed
instead.


@cindex @code{tupletNumberFormatFunction}
@cindex tuplet formatting 


@refcommands

@cindex @code{\tupletUp}
@code{\tupletUp}, 
@cindex @code{\tupletDown}
@code{\tupletDown}, 
@cindex @code{\tupletNeutral}
@code{\tupletNeutral}.

@seealso

User manual: @ref{Changing context properties on the fly} for the
@code{\set} command.


Program reference: @internalsref{TupletBracket}, and @internalsref{TimeScaledMusic}.

Examples: @inputfileref{input/@/regression,tuplet@/-nest@/.ly}.

@refbugs

Nested tuplets are not formatted automatically.  In this case, outer
tuplet brackets should be moved manually, which is demonstrated in
@inputfileref{input/@/regression,tuplet@/-nest@/.ly}.



@node Easier music entry
@section Easier music entry
@cindex Music entry

This section deals with tricks and features of the input language that
were added solely to help entering music and finding and correcting
mistakes.  There are also external tools that make debugging easier.
See @ref{Point and click} for more information.

It is also possible to enter and edit music using other programs, such as
GUI interfaces or MIDI sequencers.  Refer to the LilyPond
website for more information.


@menu
* Relative octaves::            
* Octave check::                
* Bar check::                   
* Skipping corrected music::    
* Automatic note splitting::    
@end menu




@node Relative octaves
@subsection Relative octaves
@cindex Relative
@cindex relative octave specification

Octaves are specified by adding @code{'} and @code{,} to pitch names.
When you copy existing music, it is easy to accidentally put a pitch
in the wrong octave and hard to find such an error.  The relative
octave mode prevents these errors by making the mistakes much
larger: a single error puts the rest of the piece off by one octave

@cindex @code{\relative}
@example
\relative @var{startpitch} @var{musicexpr}
@end example

@noindent
or

@example
\relative @var{musicexpr}
@end example
 
The octave of notes that appear in @var{musicexpr} are calculated as
follows: if no octave changing marks are used, the basic interval
between this and the last note is always taken to be a fourth or
less.  This distance is determined without regarding alterations; a
@code{fisis} following a @code{ceses} will be put above the
@code{ceses}.  In other words, a doubly-augmented fourth is considered
a smaller interval than a diminshed fifth, even though the fourth is
seven semitones while the fifth is only six semitones.

The octave changing marks @code{'} and @code{,} can be added to raise
or lower the pitch by an extra octave.  Upon entering relative mode,
an absolute starting pitch can be specified that will act as the
predecessor of the first note of @var{musicexpr}.  If no starting pitch
is specified, then middle C is used as a start.

Here is the relative mode shown in action
@lilypond[quote,fragment,raggedright,verbatim]
\relative c'' {
  b c d c b c bes a 
}
@end lilypond

Octave changing marks are used for intervals greater than a fourth
@lilypond[quote,raggedright,fragment,verbatim]
\relative c'' {
  c g c f, c' a, e''
}
@end lilypond

If the preceding item is a chord, the first note of the chord is used
to determine the first note of the next chord

@lilypond[quote,raggedright,fragment,verbatim]
\relative c' {
  c <c e g> 
  <c' e g>
  <c, e' g>
}
@end lilypond

The pitch after the @code{\relative} contains a note name.


The relative conversion will not affect @code{\transpose},
@code{\chordmode} or @code{\relative} sections in its argument.  To use
relative within transposed music, an additional @code{\relative} must
be placed inside @code{\transpose}.

@node Octave check
@subsection Octave check


Octave checks make octave errors easier to correct:  a note may be
followed by @code{=}@var{quotes} which indicates what its absolute
octave should be.  In the following example,
@example
\relative c'' @{ c='' b=' d,='' @}        
@end example

@noindent
@c take care with @code, adds confusing quotes.
the @code{d} will generate a warning, because a @code{d''} is expected
(because @code{b'} to @code{d''} is only a third), but a @code{d}' is
found.  In the output, the octave is corrected to be a @code{d''} and
the next note is calculated relative to @code{d''} instead of @code{d'}.



There is also a syntax that is separate from the notes.  The syntax

@example
\octave @var{pitch}
@end example

This checks that @var{pitch} (without quotes) yields @var{pitch} (with
quotes) in \relative mode.  If not, a warning is printed, and the
octave is corrected.

In the example below, the first check passes without incident, since
the @code{e} (in relative mode) is within a fifth of @code{a'}.  However,
the second check produces a warning, since the @code{e} is not within
a fifth of @code{b'}.  The warning message is printed, and the octave
is adjusted so that the following notes are in the correct octave
once again.

@example
\relative c' @{
  e
  \octave a'
  \octave b'
@}
@end example


The octave of a note following an octave check is determined with
respect to the note preceding it.  In the next fragment, the last note
is a @code{a'}, above middle C.  That means that the @code{\octave}
check passes successfully, so the check could be deleted without changing
the output of the piece.

@lilypond[quote,raggedright,verbatim,fragment] 
\relative c' {
  e
  \octave b
  a        
}
@end lilypond

@node Bar check
@subsection Bar check
@cindex Bar check

@cindex bar check
@cindex @code{barCheckSynchronize}
@cindex @code{|}

Bar checks help detect errors in the durations.  A bar check is
entered using the bar symbol, `@code{|}'.  Whenever it is encountered
during interpretation, it should fall on a measure boundary.  If it
does not, a warning is printed.  In the next example, the second bar
check will signal an error
@example
\time 3/4 c2 e4 | g2 | 
@end example

Bar checks can also be used in lyrics, for example 

@example
\lyricmode @{
  \time 2/4
  Twin -- kle | Twin -- kle
@} 
@end example


@cindex @code{skipTypesetting}

Failed bar checks are caused by entering incorrect
durations.  Incorrect durations often completely garble up the score,
especially if the score is polyphonic, so a good place to start correcting
input is by scanning for failed bar checks and incorrect durations.  To
speed up this process, the @code{skipTypesetting} feature may be
used.  It is described in the next section.

@cindex @code{|}
@cindex @code{pipeSymbol}

It is also possible to redefine the meaning of @code{|}.  This is done
by assigning a music expression to @code{pipeSymbol},

@lilypond[quote,raggedright,verbatim]
pipeSymbol = \bar "||"

{ c'2 c' | c'2 c }
@end lilypond 


@node Skipping corrected music
@subsection Skipping corrected music

The property @code{Score.skipTypesetting} can be used to switch on and
off typesetting completely during the interpretation phase.  When
typesetting is switched off, the music is processed much more
quickly.  This can be used to skip over the parts of a score that
have already been checked for errors

@lilypond[quote,fragment,raggedright,verbatim]
\relative c'' {
  c8 d
  \set Score.skipTypesetting = ##t
  e e e e e e e e
  \set Score.skipTypesetting = ##f
  c d b bes a g c2 }
@end lilypond

In polyphonic music, @code{Score.skipTypesetting} will affect all
voices and staves, saving even more time.

@node Automatic note splitting
@subsection Automatic note splitting

Long notes can be converted automatically to tied notes.  This is done
by replacing the @internalsref{Note_heads_engraver} by the
@internalsref{Completion_heads_engraver}.
In the following examples, notes crossing the bar line are split and tied.


@lilypond[quote,fragment,verbatim,relative=1,linewidth=12\cm]
\new Voice \with {
  \remove "Note_heads_engraver"
  \consists "Completion_heads_engraver"
} {
  c2. c8 d4 e f g a b c8 c2 b4 a g16 f4 e d c8. c2 
}
@end lilypond

This engraver splits all running notes at the bar line, and inserts
ties.  One of its uses is to debug complex scores: if the measures are
not entirely filled, then the ties exactly show how much each measure
is off.

@refbugs

Not all durations (especially those containing tuplets) can be
represented exactly with normal notes and dots, but the engraver will
not insert tuplets.

@seealso

Examples: @inputfileref{input/@/regression,completion@/-heads@/.ly}.

@noindent

Program reference: @internalsref{Completion_heads_engraver}.


@node Staff notation
@section Staff notation

This section describes music notation that occurs on staff level,
such as key signatures, clefs and time signatures.

@cindex Staff notation

@menu
* Staff symbol::                
* Key signature::               
* Clef::                        
* Ottava brackets::             
* Time signature::              
* Partial measures::            
* Unmetered music::             
* Bar lines::                   
* Time administration::         
* Controlling formatting of prefatory matter::  
@end menu

@node Staff symbol
@subsection Staff symbol

@cindex adjusting staff symbol

Notes, dynamic signs, etc. are grouped
with a set of horizontal lines, into a staff (plural `staves').  In our
system, these lines are drawn using a separate layout object called
staff symbol.  


@cindex staff lines, setting number of
@cindex staff lines, setting thickness of
@cindex thickness of staff lines, setting 
@cindex number of staff lines, setting 

@seealso

Program reference: @internalsref{StaffSymbol}.

Examples: @inputfileref{input/@/test,staff@/-lines@/.ly},
@inputfileref{input/@/test,staff@/-size@/.ly}.

@refbugs

If a staff is ended halfway a piece, the staff symbol may not end
exactly on the bar line.


@node Key signature
@subsection Key signature
@cindex Key signature

@cindex @code{\key}

The key signature indicates the tonality in which a piece is played.  It
is denoted by a set of alterations (flats or sharps) at the start of the
staff.


Setting or changing the key signature is done with the @code{\key}
command
@example
  @code{\key} @var{pitch} @var{type}
@end example

@cindex @code{\minor}
@cindex @code{\major}
@cindex @code{\minor}
@cindex @code{\ionian}
@cindex @code{\locrian}
@cindex @code{\aeolian}
@cindex @code{\mixolydian}
@cindex @code{\lydian}
@cindex @code{\phrygian}
@cindex @code{\dorian}

Here, @var{type} should be @code{\major} or @code{\minor} to get
@var{pitch}-major or @var{pitch}-minor, respectively.
The standard mode names @code{\ionian},
@code{\locrian}, @code{\aeolian}, @code{\mixolydian}, @code{\lydian},
@code{\phrygian}, and @code{\dorian} are also defined.

This command sets the context property
@internalsref{Staff}.@code{keySignature}.  Non-standard key signatures
can be specified by setting this property directly.

Accidentals and key signatures often confuse new users, because
unaltered notes get natural signs depending on the key signature.  For
more information, see @ref{More about pitches}.

@seealso

Program reference: @internalsref{KeyChangeEvent},
@internalsref{KeyCancellation} and @internalsref{KeySignature}.

@cindex @code{keySignature}


@node Clef
@subsection Clef
@cindex @code{\clef}

The clef indicates which lines of the staff correspond to which
pitches.


The clef can be set with the @code{\clef} command
@lilypond[quote,raggedright,fragment,verbatim]
{ c''2 \clef alto g'2 }
@end lilypond

Supported clef-names include
@c Moved standard clefs to the top /MB
@table @code
@cindex treble clef
@cindex violin clef
@item treble, violin, G, G2
G clef on 2nd line
@item alto, C
@cindex alto clef 
 C clef on 3rd line
@item tenor
@cindex tenor clef 
 C clef on 4th line. 
@item bass, F
@cindex bass clef
 F clef on 4th line
@item french
@cindex french clef
 G clef on 1st line, so-called French violin clef
@item soprano
@cindex soprano clef
 C clef on 1st line
@item mezzosoprano
@cindex mezzosoprano clef
 C clef on 2nd line
@item baritone
@cindex baritone clef
 C clef on 5th line
@item varbaritone
@cindex varbaritone clef
 F clef on 3rd line
@item subbass
@cindex subbass clef
 F clef on 5th line
@item percussion
 percussion clef
@item tab
 tablature clef
@end table

By adding @code{_8} or @code{^8} to the clef name, the clef is
transposed one octave down or up, respectively, and @code{_15} and
@code{^15} transposes by two octaves.  The argument @var{clefname}
must be enclosed in quotes when it contains underscores or digits.  For
example,


@cindex choral tenor clef  
@lilypond[quote,raggedright,verbatim,fragment,relative=1]
\clef "G_8" c4
@end lilypond

This command is equivalent to setting @code{clefGlyph},
@code{clefPosition} (which controls the Y position of the clef),
@code{centralCPosition} and @code{clefOctavation}.  A clef is printed
when any of these properties are changed.  The following example shows
possibilities when setting properties manually.

@lilypond[quote,raggedright,verbatim]
{
  \set Staff.clefGlyph = #"clefs-F"
  \set Staff.clefPosition = #2
  c'4
  \set Staff.clefGlyph = #"clefs-G"
  c'4
  \set Staff.clefGlyph = #"clefs-C"
  c'4
  \set Staff.clefOctavation = #7 
  c'4
  \set Staff.clefOctavation = #0 
  \set Staff.clefPosition = #0
  c'4
  \clef "bass"
  c'4
}
@end lilypond


@seealso

Program reference: @internalsref{Clef}.



@node Ottava brackets
@subsection Ottava brackets

`Ottava' brackets introduce an extra transposition of an octave for
the staff.  They are created by invoking the function
@code{set-octavation}

@cindex ottava
@cindex 15ma
@cindex octavation

@lilypond[quote,raggedright,verbatim,fragment]
\relative c''' {
  a2 b
  #(set-octavation 1)
  a b 
  #(set-octavation 0)
  a b
}
@end lilypond

The @code{set-octavation} function also takes -1 (for 8va bassa) and 2
(for 15ma) as arguments.  Internally the function sets the properties
@code{ottavation} (e.g. to @code{"8va"}) and
@code{centralCPosition}.  For overriding the text of the bracket, set
@code{ottavation} after invoking @code{set-octavation}, i.e.,

@lilypond[quote,raggedright,verbatim]
{
  #(set-octavation 1)
  \set Staff.ottavation = #"8"
  c'''
}
@end lilypond

@seealso

Program reference: @internalsref{OttavaBracket}.

Examples: @inputfileref{input/@/regression,ottava@/.ly},
@inputfileref{input/@/regression,ottava@/-broken@/.ly}.

@refbugs

@code{set-octavation} will get confused when clef changes happen
during an octavation bracket.




@node Time signature
@subsection Time signature
@cindex Time signature
@cindex meter
@cindex @code{\time}

Time signature indicates the metrum of a piece: a regular pattern of
strong and weak beats.  It is denoted by a fraction at the start of the
staff.


The time signature is set or changed by the @code{\time}
command
@lilypond[quote,raggedright,fragment,verbatim]
\time 2/4 c'2 \time 3/4 c'2. 
@end lilypond

The symbol that is printed can be customized with the @code{style}
property.  Setting it to @code{#'()} uses fraction style for 4/4 and
2/2 time,

@lilypond[fragment,quote,raggedright,verbatim]
\time 4/4 c'1
\time 2/2 c'1
\override Staff.TimeSignature #'style = #'()
\time 4/4 c'1
\time 2/2 c'1
@end lilypond



There are many more options for its layout.  See @ref{Ancient time
signatures} for more examples.


This command sets the property @code{timeSignatureFraction},
@code{beatLength} and @code{measureLength} in the @code{Timing}
context, which is normally aliased to @internalsref{Score}.  The
property @code{measureLength} determines where bar lines should be
inserted, and how automatic beams should be generated.  Changing the
value of @code{timeSignatureFraction} also causes the symbol to be
printed.

More options are available through the Scheme function
@code{set-time-signature}.  In combination with the
@internalsref{Measure_grouping_engraver}, it will create
@internalsref{MeasureGrouping} signs.  Such signs ease reading
rhythmically complex modern music.  In the following example, the 9/8
measure is subdivided in 2, 2, 2 and 3.  This is passed to
@code{set-time-signature} as the third argument @code{(2 2 2 3)}

@lilypond[quote,raggedright,verbatim]
\score {
  \relative c'' {
    #(set-time-signature 9 8 '(2 2 2 3))
    g8[ g] d[ d] g[ g] a8[( bes g]) | 
    #(set-time-signature 5 8 '(3 2))
    a4. g4
  }
  \layout {
    \context {
      \Staff
      \consists "Measure_grouping_engraver"
    }
  }
}
@end lilypond

@seealso

Program reference: @internalsref{TimeSignature}, and @internalsref{Timing_engraver}.


@refbugs

Automatic beaming does not use the measure grouping specified with
@code{set-time-signature}.

@node Partial measures
@subsection Partial measures
@cindex Partial
@cindex anacrusis
@cindex partial measure
@cindex measure, partial
@cindex shorten measures
@cindex @code{\partial}

Partial measures, for example in upsteps, are entered using the
@code{\partial} command
@lilypond[quote,raggedright,fragment,verbatim,relative=2]
\partial 16*5  c16 cis d dis e | a2. c,4 | b2
@end lilypond

The syntax for this command is 
@example
  \partial @var{duration} 
@end example
This is internally translated into
@example
  \set Timing.measurePosition = -@var{length of duration}
@end example
@cindex @code{|}
The property @code{measurePosition} contains a rational number
indicating how much of the measure has passed at this point.

@refbugs

This command does not take into account grace notes at the start of
the music.  When a piece starts with graces notes in the pickup, then
the @code{\partial} should follow the grace notes

@lilypond[verbatim,quote,raggedright,relative,fragment]
{
  \grace f16 
  \partial 4
  g4
  a2 g2 
}
@end lilypond


@node Unmetered music
@subsection Unmetered music

@cindex @code{\bar}

Bar lines and bar numbers are calculated automatically.  For unmetered
music (e.g. cadenzas), this is not desirable.  By setting
@code{Score.timing} to false, this automatic timing can be switched
off.  Empty bar lines,

@example
  \bar ""
@end example

@noindent
indicate where line breaks can occur.

@refcommands

@cindex @code{\cadenzaOn}
@code{\cadenzaOn}, 
@cindex @code{\cadenzaOff}
@code{\cadenzaOff}.




@node Bar lines
@subsection Bar lines
@cindex Bar lines

@cindex @code{\bar}
@cindex measure lines
@cindex repeat bars


Bar lines delimit measures, but are also used to indicate repeats.
Normally, they are inserted automatically.  Line breaks may only
happen on bar lines.

Special types of bar lines can be forced with the @code{\bar} command
@c
@lilypond[quote,raggedright,relative=2,fragment,verbatim]
c4 \bar "|:" c4
@end lilypond

The following bar types are available
@lilypondfile[raggedright,quote]{bar-lines.ly}

For allowing line breaks, there is a special command,
@example
  \bar ""
@end example 
This will insert an invisible bar line, and allow line breaks at this
point.

In scores with many staves, a @code{\bar} command in one staff is
automatically applied to all staves.  The resulting bar lines are
connected between different staves of a @internalsref{StaffGroup}
@c
@lilypond[quote,raggedright,fragment,verbatim]
<<
  \context StaffGroup <<
    \new Staff {
      e'4 d'
      \bar "||"
      f' e'
    }
    \new Staff { \clef bass c4 g e g }
  >>
  \new Staff { \clef bass c2 c2 }
>>
@end lilypond


The command @code{\bar }@var{bartype} is a short cut for doing
@code{\set Timing.whichBar = }@var{bartype}.  Whenever @code{whichBar}
is set to a string, a bar line of that type is created.

A bar line is created whenever the @code{whichBar} property is set.
At the start of a measure it is set to the contents of
@code{Timing.defaultBarType}.  The contents of @code{repeatCommands} are used
to override default measure bars.

@cindex @code{whichBar}
@cindex @code{repeatCommands}
@cindex @code{defaultBarType}

You are encouraged to use @code{\repeat} for repetitions.  See
@ref{Repeats}.



@seealso

In this manual: @ref{Repeats}, @ref{System start delimiters}


Program reference: @internalsref{BarLine} (created at
@internalsref{Staff} level), @internalsref{SpanBar} (across staves).

@cindex bar lines at start of system
@cindex start of system



Examples: @inputfileref{input/@/test,bar@/-lines@/.ly},


@node Time administration
@subsection Time administration

Time is administered by the @internalsref{Time_signature_engraver},
which usually lives in the @internalsref{Score} context.
The bookkeeping deals with the following variables

@table @code
@item currentBarNumber
 the measure number
@item measureLength
  the length of the measures in the current time signature.  For a 4/4
  time this is 1, and for 6/8 it is 3/4.
@item measurePosition
  the point within the measure where we currently are.  This quantity
  is reset to 0 whenever it exceeds @code{measureLength}.  When that happens,
  @code{currentBarNumber} is incremented.
@item timing
 if set to true, the above variables are updated for every time
 step.  When set to false, the engraver stays in the current measure
 indefinitely.
@end table

Timing can be changed by setting any of these variables explicitly.
In the next example, the 4/4 time signature is printed, but
@code{measureLength} is set to 5/4.  After a while, the measure is
shortened by 1/8, by setting @code{measurePosition} to -3/8 at 2/4 in
the measure, so the next bar line will fall at 2/4 + 3/8. 

@lilypond[raggedright,verbatim,relative,fragment]
  \set Score.measureLength = #(ly:make-moment 5 4)
  c1 c4
  c1 c4 
  c4 c4
  \set Score.measurePosition = #(ly:make-moment -3 8)
  b8 b b
  c4 c1
@end lilypond


@node Controlling formatting of prefatory matter
@subsection Controlling formatting of prefatory matter

TODO  Somebody needs to explain this example, but I don't know what
they're trying to do, so it won't be me.  -gp

@lilypond[verbatim]
\transpose c c' {
        \override Staff.Clef  #'break-visibility = #end-of-line-visible
        \override Staff.KeySignature  #'break-visibility = #end-of-line-visible
        \set Staff.explicitClefVisibility = #end-of-line-visible
        \set Staff.explicitKeySignatureVisibility = #end-of-line-visible

        % We want the time sig to take space, otherwise there is not
        % enough white at the start of the line.
        %
        
        \override Staff.TimeSignature  #'transparent = ##t
        \set Score.defaultBarType = #"empty"
        
        c1 d e f g a b c
        \key d \major
        \break

        % see above.
        \time 4/4
        
        d e fis g a b cis d 
        \key g \major
        \break
        \time 4/4    
}
@end lilypond


@node Polyphony
@section Polyphony

Polyphony in music refers to having more than one voice occuring in
a piece of music.  Polyphony in LilyPond refers to having more than
one voice on the same staff.

@menu
* Writing polyphonic music::
@end menu

@node Writing polyphonic music
@subsection Writing polyphonic music
@cindex polyphony

The easiest way to enter fragments with more than one voice on a staff
is to split chords using the separator @code{\\}.  You can use it for
small, short-lived voices or for single chords

@cindex @code{\\}

@lilypond[quote,raggedright,verbatim,fragment]
\context Staff \relative c'' {
  c4 << { f d e  } \\ { b c2 } >>
  c4 << g' \\ b, \\  f' \\ d >>
}
@end lilypond

The separator causes @internalsref{Voice} contexts@footnote{Polyphonic
voices are sometimes called ``layers'' in other notation packages}
@cindex layers
to be instantiated.  They bear the names @code{"1"}, @code{"2"}, etc.  In
each of these contexts, vertical direction of slurs, stems, etc. is set
appropriately.

@cindex @code{\voiceOne}
@cindex @code{\voiceFour}

This can also be done by instantiating @internalsref{Voice} contexts
by hand, and using @code{\voiceOne}, up to @code{\voiceFour} to assign
a stem directions and horizontal shift for each part
@c

@lilypond[quote,raggedright,verbatim]
\relative c''
\context Staff <<
  \new Voice { \voiceOne cis2 b  }
  \new Voice { \voiceThree b4 ais ~ ais4 gis4 } 
  \new Voice { \voiceTwo fis4~  fis4 f ~ f  } >>
@end lilypond

@noindent
The command @code{\oneVoice} will revert back to the normal setting.
@cindex @code{\oneVoice}


Normally, note heads with a different number of dots are not merged, but
when the object property @code{merge-differently-dotted} is set in
the @internalsref{NoteCollision} object, they are merged
@lilypond[quote,verbatim,fragment,raggedright,relative=2]
\context Voice << {
  g8 g8 
  \override Staff.NoteCollision  
    #'merge-differently-dotted = ##t
  g8 g8
} \\ { g8.[ f16] g8.[ f16] } >>
@end lilypond

Similarly, you can merge half note heads with eighth notes, by setting
@code{merge-differently-headed}
@lilypond[quote,raggedright,fragment,relative=2,verbatim]
\context Voice << {
  c8 c4.
  \override Staff.NoteCollision
    #'merge-differently-headed = ##t
c8 c4. } \\ { c2 c2 } >>
@end lilypond

LilyPond also vertically shifts rests that are opposite of a stem,
for example

@lilypond[quote,raggedright,fragment,verbatim]
\context Voice << c''4 \\  r4 >>
@end lilypond


@refcommands



@cindex @code{\oneVoice}
@code{\oneVoice}, 
@cindex @code{\voiceOne}
@code{\voiceOne}, 
@cindex @code{\voiceTwo}
@code{\voiceTwo}, 
@cindex @code{\voiceThree}
@code{\voiceThree}, 
@cindex @code{\voiceFour}
@code{\voiceFour}.



@cindex @code{\shiftOn}
@code{\shiftOn}, 
@cindex @code{\shiftOnn}
@code{\shiftOnn}, 
@cindex @code{\shiftOnnn}
@code{\shiftOnnn}, 
@cindex @code{\shiftOff}
@code{\shiftOff}: these commands specify in what chords of the current
voice should be shifted.  The outer voices (normally: voice one and
two) have @code{\shiftOff}, while the inner voices (three and four)
have @code{\shiftOn}.  @code{\shiftOnn} and @code{\shiftOnnn} define
further shift levels.


When LilyPond cannot cope, the @code{force-hshift}
property of the @internalsref{NoteColumn} object and pitched rests can
be used to override typesetting decisions.

@lilypond[verbatim,raggedright]
\relative <<
{
  <d g>
  <d g>
} \\ {
  <b f'>
  \once \override NoteColumn  #'force-hshift = #1.7
  <b f'>
} >> 
@end lilypond



@seealso

Program reference: the objects responsible for resolving collisions are
@internalsref{NoteCollision} and @internalsref{RestCollision}.

Examples: 
@inputfileref{input/@/regression,collision@/-dots@/.ly},
@inputfileref{input/@/regression,collision@/-head-chords@/.ly},
@inputfileref{input/@/regression,collision@/-heads@/.ly},
@inputfileref{input/@/regression,collision@/-mesh@/.ly}, and
@inputfileref{input/@/regression,collisions@/.ly}.


@refbugs


When using @code{merge-differently-headed} with an upstem eighth or a
shorter note, and a downstem half note, the eighth note gets the wrong
offset.

There is no support for clusters where the same note occurs with
different accidentals in the same chord.  In this case, it is
recommended to use enharmonic transcription, or to use special cluster
notation (see @ref{Clusters}).

@node Beaming
@section Beaming

Beams are used to group short notes into chunks that are aligned with
the metrum.  LilyPond normally inserts beams automatically, but if you
wish you may control them manually or changed how beams are automatically
grouped.

@cindex Automatic beams
@menu
* Automatic beams::
* Manual beams::                
* Setting automatic beam behavior::  
* Beam formatting::             
@end menu

@node Automatic beams
@subsection Automatic beams

LilyPond inserts beams automatically

@lilypond[quote,raggedright,fragment,verbatim,relative=2]
\time 2/4 c8 c c c \time 6/8 c c c c8. c16  c8
@end lilypond

When these automatic decisions are not good enough, beaming can be
entered explicitly.  It is also possible to define beaming patterns
that differ from the defaults.

Individual notes may be marked with @code{\noBeam}, to prevent them
from being beamed

@lilypond[quote,raggedright,fragment,verbatim,relative=2]
\time 2/4 c8 c\noBeam c c
@end lilypond


@seealso

Program reference: @internalsref{Beam}. 


@node Manual beams
@subsection Manual beams
@cindex beams, manual
@cindex @code{]}
@cindex @code{[}

In some cases it may be necessary to override the automatic beaming
algorithm.  For example, the autobeamer will not put beams over rests
or bar lines.  Such beams are specified manually by marking the begin
and end point with @code{[} and @code{]}

@lilypond[quote,raggedright,fragment,relative=1,verbatim]
{
  r4 r8[ g' a r8] r8 g[ | a] r8
}
@end lilypond

@cindex @code{stemLeftBeamCount}

Normally, beaming patterns within a beam are determined automatically.
If necessary, the properties @code{stemLeftBeamCount} and
@code{stemRightBeamCount} can be used to override the defaults.  If
either property is set, its value will be used only once, and then it
is erased

@lilypond[quote,raggedright,fragment,relative=1,verbatim]
{
   f8[ r16
      f g a]
   f8[ r16
   \set stemLeftBeamCount = #1
      f g a]
}
@end lilypond
@cindex @code{stemRightBeamCount}


The property @code{subdivideBeams} can be set in order to subdivide
all 16th or shorter beams at beat positions, as defined by the
@code{beatLength} property.


@lilypond[fragment,quote,relative=2,verbatim]
c16[ c c c c c c c]
\set subdivideBeams = ##t
c16[ c c c c c c c]
\set Score.beatLength = #(ly:make-moment 1 8)
c16[ c c c c c c c]
@end lilypond
@cindex @code{subdivideBeams}

Normally, line breaks are forbidden when beams cross bar lines.  This
behavior can be changed by setting @code{allowBeamBreak}.

@cindex @code{allowBeamBreak}
@cindex beams and line breaks

@cindex beams, kneed
@cindex kneed beams
@cindex auto-knee-gap


@seealso

User manual: @ref{Changing context properties on the fly} for the
@code{\set} command


@refbugs

@cindex Frenched staves
Kneed beams are inserted automatically, when a large gap is detected
between the note heads.  This behavior can be tuned through the object.


Automatically kneed cross-staff beams cannot be used together with
hidden staves.  See @ref{Hiding staves}.

Beams do not avoid collisions with symbols around the notes, such as
texts and accidentals.

@c FIXME.


@node Setting automatic beam behavior
@subsection Setting automatic beam behavior 

@cindex @code{autoBeamSettings}
@cindex @code{(end * * * *)}
@cindex @code{(begin * * * *)}
@cindex automatic beams, tuning
@cindex tuning automatic beaming

@c [TODO: use \applycontext]

In normal time signatures, automatic beams can start on any note but can
only end in a few positions within the measure: beams can end on a beat,
or at durations specified by the properties in
@code{autoBeamSettings}.  The defaults for @code{autoBeamSettings}
are defined in @file{scm/@/auto@/-beam@/.scm}.

The value of @code{autoBeamSettings} is changed with two functions,
@example
  #(override-auto-beam-setting
     '(@var{be} @var{p} @var{q} @var{n} @var{m}) @var{a} @var{b}
     [@var{context}])
  #(revert-auto-beam-setting '(@var{be} @var{p} @var{q} @var{n} @var{m}))
@end example
Here, @var{be} is the symbol @code{begin} or @code{end}, and
@var{context} is an optional context (default: @code{'Voice}).  It
determines whether the rule applies to begin or end-points.  The
quantity @var{p}/@var{q} refers to the length of the beamed notes (and
`@code{* *}' designates notes of any length), @var{n}/@var{M} refers
to a time signature (wildcards `@code{* *}' may be entered to
designate all time signatures), @var{a}/@var{b} is a duration.  By
default, this command changes settings for the current voice.  It is
also possible to adjust settings at higher contexts, by adding a
@var{context} argument.

For example, if automatic beams should end on every quarter note, use
the following
@example
   #(override-auto-beam-setting '(end * * * *) 1 4 'Staff)
@end example
Since the duration of a quarter note is 1/4 of a whole note, it is
entered as @code{(ly:make-moment 1 4)}.

The same syntax can be used to specify beam starting points.  In this
example, automatic beams can only end on a dotted quarter note
@example
   #(override-auto-beam-setting '(end * * * *) 3 8)
@end example
In 4/4 time signature, this means that automatic beams could end only on
3/8 and on the fourth beat of the measure (after 3/4, that is 2 times
3/8, has passed within the measure).

Rules can also be restricted to specific time signatures.  A rule that
should only be applied in @var{N}/@var{M} time signature is formed by
replacing the second asterisks by @var{N} and @var{M}.  For example, a
rule for 6/8 time exclusively looks like
@example
 #(override-auto-beam-setting '(begin * * 6 8) @dots{})
@end example

If a rule should be to applied only to certain types of beams, use the
first pair of asterisks.  Beams are classified according to the
shortest note they contain.  For a beam ending rule that only applies
to beams with 32nd notes (and no shorter notes), use @code{(end 1 32 *
*)}.

@cindex automatic beam generation
@cindex autobeam
@cindex @code{autoBeaming}
@cindex lyrics

If beams are used to indicate melismata in songs, then automatic
beaming should be switched off.  This is done by setting
@code{autoBeaming} to @code{#f}.

@refcommands

@cindex @code{\autoBeamOff}
@code{\autoBeamOff}, 
@cindex @code{\autoBeamOn}
@code{\autoBeamOn}.


@refbugs

If a score ends while an automatic beam has not been ended and is
still accepting notes, this last beam will not be typeset at all.  The
same holds polyphonic voices, entered with @code{<< @dots{} \\ @dots{}
>>}.  If a polyphonic voice ends while an automatic beam is still
accepting notes, it is not typeset.

The rules for ending a beam depend on the shortest note in a beam.
So, while it is possible to have different ending rules for eight
beams and sixteenth beams, a beam that contains both eight and
sixteenth notes will use the rules for the sixteenth beam.

In the example below, the autobeamer makes eighth beams and sixteenth
end at three eighths.  The third beam can only be corrected by
specifying manual beaming.

@lilypond[quote,raggedright,fragment,relative=1]
#(override-auto-beam-setting '(end * * * *) 3 8)
% rather show case where it goes wrong
%\time 12/8 c'8 c c c16 c c c c c c[ c c c] c8[ c] c4
\time 12/8 c'8 c c c16 c c c c c c c c c c8 c c4
@end lilypond
It is not possible to specify beaming parameters that act differently in
different parts of a measure.  This means that it is not possible to use
automatic beaming in irregular meters such as @code{5/8}.

@node Beam formatting
@subsection Beam formatting


When a beam falls in the middle of the staff, the beams point normally
down.  However, this behaviour can be altered with the
@code{neutral-direction} property.


@lilypond[quote,raggedright,relative=2,fragment,verbatim]
{
   b8[ b]
  \override Beam  #'neutral-direction = #-1
   b[ b]
  \override Beam  #'neutral-direction = #1
   b[ b]
}
@end lilypond

@node Accidentals
@section Accidentals

This section describes how to change the way that accidentals are
inserted automatically before notes.

@menu
* Automatic accidentals::
@end menu

@node Automatic accidentals
@subsection Automatic accidentals
@cindex Automatic accidentals

Common rules for typesetting accidents have been placed in a
function.  This function is called as follows

@cindex @code{set-accidental-style}
@example
#(set-accidental-style 'STYLE #('CONTEXT#))
@end example

The function can take two arguments: the name of the accidental style,
and an optional argument that denotes the context which should be
changed.  If no context name is supplied, @code{Staff} is the default,
but you may wish to apply the accidental style to a single @code{Voice}
instead.

The following accidental styles are supported
@table @code
@item default
This is the default typesetting behavior.  It corresponds
to 18th century common practice: Accidentals are
remembered to the end of the measure in which they occur and
only on their own octave.

@item voice
The normal behavior is to remember the accidentals on
Staff-level.  This variable, however, typesets accidentals
individually for each voice.  Apart from that, the rule is similar to
@code{default}.

As a result, accidentals from one voice do not get canceled in other
voices, which is often an unwanted result

@lilypond[quote,raggedright,relative=1,fragment,verbatim]
\context Staff <<
  #(set-accidental-style 'voice)
  <<
    { es g } \\
    { c, e }
>> >>
@end lilypond

The @code{voice} option should be used if the voices
are to be read solely by individual musicians.  If the staff is to be
used by one musician (e.g. a conductor) then 
@code{modern} or @code{modern-cautionary}
should be used instead.

@item modern
@cindex @code{modern} style accidentals
This rule corresponds to the common practice in the 20th century.  This rule
prints the same accidentals as @code{default}, but temporary
accidentals also are canceled in other octaves.  Furthermore,
in the same octave, they also get canceled in the following
measure

@lilypond[quote,raggedright,fragment,verbatim]
#(set-accidental-style 'modern)
cis' c'' cis'2 | c'' c'
@end lilypond

@item @code{modern-cautionary}
@cindex @code{modern-cautionary}
This rule is similar to @code{modern}, but the ``extra'' accidentals
(the ones not typeset by @code{default}) are typeset as cautionary
accidentals.  They are printed in reduced size or with parentheses
@lilypond[quote,raggedright,fragment,verbatim]
#(set-accidental-style 'modern-cautionary)
cis' c'' cis'2 | c'' c'
@end lilypond

@cindex @code{modern-voice}
@item modern-voice
This rule is used for multivoice accidentals to be read both by musicians
playing one voice and musicians playing all voices.  Accidentals are
typeset for each voice, but they @emph{are} canceled across voices in
the same @internalsref{Staff}.

@cindex @code{modern-voice-cautionary}
@item modern-voice-cautionary
This rule is the same as @code{modern-voice}, but with the extra
accidentals (the ones not typeset by @code{voice}) typeset
as cautionaries.  Even though all accidentals typeset by
@code{default} @emph{are} typeset by this variable then
some of them are typeset as cautionaries.

@item piano
@cindex @code{piano} accidentals
This rule reflects 20th century practice for piano notation.  Very similar to
@code{modern} but accidentals also get canceled
across the staves in the same @internalsref{GrandStaff} or
@internalsref{PianoStaff}.

@item piano-cautionary
@cindex @code{#(set-accidental-style 'piano-cautionary)}
As @code{#(set-accidental-style 'piano)} but with the extra accidentals
typeset as cautionaries.

@item no-reset
@cindex @code{no-reset} accidental style
This is the same as @code{default} but with accidentals lasting
``forever'' and not only until the next measure
@lilypond[quote,raggedright,fragment,verbatim,relative=1]
#(set-accidental-style 'no-reset)
c1 cis cis c
@end lilypond

@item forget
This is sort of the opposite of @code{no-reset}: Accidentals
are not remembered at all---and hence all accidentals are
typeset relative to the key signature, regardless of what was
before in the music
      
@lilypond[quote,raggedright,fragment,verbatim,relative=1]
#(set-accidental-style 'forget)
\key d\major c4 c cis cis d d dis dis
@end lilypond
@end table


@seealso

Program reference: @internalsref{Accidental_engraver},
@internalsref{Accidental}, and @internalsref{AccidentalPlacement}.


@refbugs

Simultaneous notes are considered to be entered in sequential
mode.  This means that in a chord the accidentals are typeset as if the
notes in the chord happened once at a time - in the order in which
they appear in the input file.

This is a problem when accidentals in a chord depend on each other,
which does not happen for the default accidental style.  The problem
can be solved by manually inserting @code{!} and @code{?}  for the
problematic notes.


@node Expressive marks
@section Expressive marks


@c todo: should change ordering
@c where to put text spanners, metronome marks,
@c fingering?

Expressive marks help musicians to bring more to the music than simple
notes and rhythms.

@menu
* Slurs::                       
* Phrasing slurs::              
* Breath marks::                
* Metronome marks::             
* Text scripts::                
* Text spanners::               
* Analysis brackets::           
* Articulations::               
* Running trills::              
* Fingering instructions::      
* Grace notes::                 
* Glissando::                   
* Dynamics::                    
@end menu

@node Slurs
@subsection Slurs
@cindex Slurs

A slur indicates that notes are to be played bound or @emph{legato}.

They are entered using parentheses
@lilypond[quote,raggedright,relative=2,fragment,verbatim]
  f( g a) a8 b( a4 g2 f4)
  <c e>2( <b d>2)
@end lilypond

The direction of a slur can be set with the
generic commands

@example
  \override Slur #'direction = #UP
  \slurUp            % shortcut for the previous line 
@end example

@noindent
However, there is a convenient shorthand for forcing slur
directions.  By adding @code{_} or @code{^} before the opening
parentheses, the direction is also set.  For example,  

@lilypond[relative=2,raggedright,quote,verbatim,fragment]
  c4_( c)   c^( c)
@end lilypond

Some composers write two slurs when they want legato chords.  This can
be achieved in LilyPond by setting @code{doubleSlurs},

@lilypond[verbatim,raggedright,relative,fragment,quote]
   \set doubleSlurs = ##t
   <c e>4 ( <d f> <c e> <d f> )
@end lilypond  

 
@refcommands


@cindex @code{\slurUp}
@code{\slurUp}, 
@cindex @code{\slurDown}
@code{\slurDown}, 
@cindex @code{\slurNeutral}
@code{\slurNeutral}, 
@cindex @code{\slurDotted}
@code{\slurDotted}, 
@cindex @code{\slurSolid}
@code{\slurSolid}.

@seealso

Program reference: @seeinternals{Slur}, and @internalsref{SlurEvent}.


@node Phrasing slurs
@subsection Phrasing slurs

@cindex phrasing slurs
@cindex phrasing marks

A phrasing slur (or phrasing mark) connects chords and is used to
indicate a musical sentence.  It is written using @code{\(} and @code{\)}
respectively

@lilypond[quote,raggedright,fragment,verbatim,relative=1]
  \time 6/4 c'\( d( e) f( e)  d\) 
@end lilypond

Typographically, the phrasing slur behaves almost exactly like a
normal slur.  However, they are treated as different objects.  A
@code{\slurUp} will have no effect on a phrasing slur; instead, use
@code{\phrasingSlurUp}, @code{\phrasingSlurDown}, and
@code{\phrasingSlurNeutral}.

The commands @code{\slurUp}, @code{\slurDown}, and @code{\slurNeutral}
will only affect normal slurs and not phrasing slurs.

@refcommands

@cindex @code{\phrasingSlurUp}
@code{\phrasingSlurUp}, 
@cindex @code{\phrasingSlurDown}
@code{\phrasingSlurDown}, 
@cindex @code{\phrasingSlurNeutral}
@code{\phrasingSlurNeutral}.

@seealso

Program reference: see also @internalsref{PhrasingSlur}, and
@internalsref{PhrasingSlurEvent}.

@refbugs

Putting phrasing slurs over rests leads to spurious warnings.

@node Breath marks
@subsection Breath marks

Breath marks are entered using @code{\breathe}


@lilypond[quote,raggedright,fragment,relative=1,verbatim]
  c'4 \breathe d4
@end lilypond

The glyph of the breath mark can be tuned by overriding the
@code{text} property of the @code{BreathingSign} layout object with
any markup text.  For example,
@lilypond[quote,raggedright,fragment,verbatim,relative=1]
  c'4
  \override BreathingSign #'text
    = #(make-musicglyph-markup "scripts-rvarcomma")
  \breathe
  d4
@end lilypond

@seealso 

Program reference: @internalsref{BreathingSign},
@internalsref{BreathingSignEvent}.

Examples: @inputfileref{input/@/regression,breathing@/-sign@/.ly}.


@node Metronome marks
@subsection Metronome marks

@cindex Tempo
@cindex beats per minute
@cindex metronome marking

Metronome settings can be entered as follows
@example 
  \tempo @var{duration} = @var{per-minute} 
@end example

In the MIDI output, they are interpreted as a tempo change.  In the
layout output, a metronome marking is printed
@cindex @code{\tempo}
@lilypond[quote,raggedright,verbatim,fragment]
  \tempo 8.=120 c''1
@end lilypond

@seealso

Program reference: @internalsref{MetronomeChangeEvent}.
  

@node Text scripts
@subsection Text scripts
@cindex Text scripts

@cindex text items, non-empty
@cindex non-empty texts

It is possible to place arbitrary strings of text or markup text (see
@ref{Text markup}) above or below notes by using a string
@code{c^"text"}.  By default, these indications do not influence the
note spacing, but by using the command @code{\fatText}, the widths
will be taken into account
@c
@lilypond[quote,fragment,raggedright,verbatim,relative=1]
  c4^"longtext" \fatText c4_"longlongtext" c4
@end lilypond

More complex formatting may also be added to a note by using the
markup command,
@lilypond[fragment,raggedright,verbatim,quote]
  c'4^\markup { bla \bold bla }
@end lilypond

The @code{\markup} is described in more detail in
@ref{Text markup}.
 

@refcommands

@cindex @code{\fatText}
@code{\fatText}, 
@cindex @code{\emptyText}
@code{\emptyText}.

@seealso

In this manual: @ref{Text markup}.

Program reference: @internalsref{TextScriptEvent}, @internalsref{TextScript}.


@node Text spanners
@subsection Text spanners
@cindex Text spanners

Some performance indications, e.g. @i{rallentando} or @i{accelerando},
are written as text and are extended over many measures with dotted
lines.  Such texts are created using text spanners; attach
@code{\startTextSpan} and @code{\stopTextSpan} to the first and last
notes of the spanner.

The string to be printed, as well as the style, is set through object
properties

@lilypond[quote,raggedright,fragment,relative=1,verbatim]
  c1 
  \override TextSpanner #'direction = #-1
  \override TextSpanner #'edge-text = #'("rall " . "")
  c2\startTextSpan b c\stopTextSpan a
@end lilypond


@seealso

Internals @internalsref{TextSpanEvent},
@internalsref{TextSpanner}.

Examples: @inputfileref{input/@/regression,text@/-spanner@/.ly}.


@node Analysis brackets
@subsection Analysis brackets
@cindex brackets
@cindex phrasing brackets
@cindex musicological analysis
@cindex note grouping bracket

Brackets are used in musical analysis to indicate structure in musical
pieces.  LilyPond supports a simple form of nested horizontal
brackets.  To use this, add the @internalsref{Horizontal_bracket_engraver}
to @internalsref{Staff} context.  A bracket is started with
@code{\startGroup} and closed with @code{\stopGroup}

@lilypond[quote,raggedright,verbatim]
\score {
  \relative c'' {  
    c4\startGroup\startGroup
    c4\stopGroup
    c4\startGroup
    c4\stopGroup\stopGroup
  }
  \layout {
    \context {
      \Staff \consists "Horizontal_bracket_engraver"
}}}
@end lilypond

@seealso

Program reference: @internalsref{HorizontalBracket},
@internalsref{NoteGroupingEvent}.

Examples: @inputfileref{input/@/regression,note@/-group@/-bracket@/.ly}. 


@node Articulations
@subsection Articulations
@cindex Articulations

@cindex articulations
@cindex scripts
@cindex ornaments

A variety of symbols can appear above and below notes to indicate
different characteristics of the performance.  They are added to a note
by adding a dash and the character signifying the
articulation.  They are demonstrated here

@lilypondfile[quote,raggedright]{script-abbreviations.ly}

The meanings of these shorthands can be changed.  See
@file{ly/@/script@/-init@/.ly} for examples.


The script is automatically placed, but the direction can be forced as
well.  Like other pieces of LilyPond code, @code{_} will place them
below the staff, and @code{^} will place them above.


@lilypond[quote,raggedright,fragment,verbatim]
  c''4^^ c''4_^
@end lilypond

Other symbols can be added using the syntax
@var{note}@code{\}@var{name}.  Again, they
can be forced up or down using @code{^} and @code{_},
e.g.

@lilypond[quote,raggedright,verbatim,fragment,relative=2]
  c\fermata c^\fermata c_\fermata
@end lilypond



@cindex accent
@cindex marcato
@cindex staccatissimo
@cindex fermata
@cindex stopped
@cindex staccato
@cindex portato
@cindex tenuto
@cindex upbow
@cindex downbow
@cindex foot marks
@cindex organ pedal marks
@cindex turn
@cindex open
@cindex flageolet
@cindex reverseturn
@cindex trill
@cindex prall
@cindex mordent
@cindex prallprall
@cindex prallmordent
@cindex prall, up
@cindex prall, down
@cindex mordent
@cindex thumb marking
@cindex segno
@cindex coda
@cindex varcoda

Here is a chart showing all scripts available,

@lilypondfile[raggedright,quote]{script-chart.ly}


The vertical ordering of scripts is controlled with the
@code{script-priority} property.  The lower this number, the closer it
will be put to the note.  In this example, the
@internalsref{TextScript} (the sharp symbol) first has the lowest
priority, so it is put lowest in the first example.  In the second, the
prall trill (the @internalsref{Script}) has the lowest, so it on the
inside.  When two objects have the same priority, the order in which
they are entered decides which one comes first.


@lilypond[verbatim,relative=3,raggedright,fragment,quote]
  \once \override TextScript #'script-priority = #-100
  a4^\prall^\markup { \sharp }
    
  \once \override Script  #'script-priority = #-100
  a4^\prall^\markup { \sharp }
@end lilypond




@seealso

Program reference: @internalsref{ScriptEvent}, and @internalsref{Script}.

@refbugs

These signs appear in the printed output but have no effect on the
MIDI rendering of the music.



@node  Running trills
@subsection Running trills

Long running trills are made with @code{\startTrillSpan} and
@code{\stopTrillSpan},


@lilypond[verbatim,raggedright,relative=2,quote,fragment]
\new Voice {
  << { c1 \startTrillSpan }
     { s2. \grace { d16[\stopTrillSpan e] } } >>
  c4 }
@end lilypond

@refcommands

@code{\startTrillSpan},
@cindex @code{\startTrillSpan}
@code{\stopTrillSpan}.
@cindex @code{\stopTrillSpan}

@seealso

Program reference: @internalsref{TrillSpanner},
@internalsref{TrillSpanEvent}.

@node Fingering instructions
@subsection Fingering instructions

@cindex fingering

Fingering instructions can be entered using
@example
  @var{note}-@var{digit}
@end example
For finger changes, use markup texts
@c
@lilypond[quote,verbatim,raggedright,fragment,relative=1]
  c4-1 c-2 c-3 c-4
  c^\markup { \finger "2-3" }
@end lilypond

@cindex finger change
@cindex scripts
@cindex superscript
@cindex subscript

You can use the thumb-script to indicate that a note should be
played with the thumb (e.g. in cello music)

@lilypond[quote,verbatim,raggedright,fragment,relative=2]
  <a_\thumb a'-3>8 <b_\thumb b'-3>
@end lilypond

Fingerings for chords can also be added to individual notes
of the chord by adding them after the pitches
@lilypond[quote,verbatim,raggedright,fragment,relative=2]
  < c-1 e-2 g-3 b-5 >4
@end lilypond

@noindent
In this case, setting @code{fingeringOrientations} will put fingerings next
to note heads

@lilypond[quote,verbatim,raggedright,fragment,relative=1]
  \set fingeringOrientations = #'(left down)
  <c-1 es-2 g-4 bes-5 > 4
  \set fingeringOrientations = #'(up right down)
  <c-1 es-2 g-4 bes-5 > 4
@end lilypond

Using this feature, it is also possible to put fingering instructions
very close to note heads in monophonic music,

@lilypond[verbatim,raggedright,quote,fragment]
  \set fingeringOrientations = #'(right)
  <es'-2>4
@end lilypond

        
@seealso

Program reference: @internalsref{FingerEvent}, and @internalsref{Fingering}.

Examples: @inputfileref{input/@/regression,finger@/-chords@/.ly}.




@node Grace notes
@subsection Grace notes


@c should have blurb about accaciatura / appogiatura

@cindex @code{\grace}
@cindex ornaments
@cindex grace notes

Grace notes are ornaments that are written out.  The most common ones
are acciaccatura, which should be played as very short.  It is denoted
by a slurred small note with a slashed stem.  The appoggiatura is a
grace note that takes a fixed fraction of the main note, and is
denoted as a slurred note in small print without a slash.  They
are entered with the commands @code{\acciaccatura} and
@code{\appoggiatura}, as demonstrated in the following example


@cindex appoggiatura
@cindex acciaccatura

@lilypond[quote,raggedright,relative=2,verbatim,fragment]
  b4 \acciaccatura d8 c4 \appoggiatura e8 d4
  \acciaccatura { g16[ f] } e4
@end lilypond

Both are special forms of the @code{\grace} command.  By prefixing this
keyword to a music expression, a new one is formed, which will be
printed in a smaller font and takes up no logical time in a measure.

@lilypond[quote,raggedright,relative=2,verbatim,fragment]
  c4 \grace c16 c4
  \grace { c16[ d16] } c2 c4
@end lilypond

@noindent
Unlike @code{\acciaccatura} and @code{\appoggiatura}, the
@code{\grace} command does not start a slur.

Internally, timing for grace notes is done using a second, `grace'
time.  Every point in time consists of two rational numbers: one
denotes the logical time, one denotes the grace timing.  The above
example is shown here with timing tuples

@lilypond[quote,raggedright]
<<
  \relative c''{ 
    c4 \grace c16  c4  \grace {
    c16[  d16] } c2 c4
  }
  \new Lyrics \lyricmode {
    \override LyricText #'font-family = #'typewriter
    
    \markup { (0,0) } 4
    \grace { \markup {
      ( \fraction 1 4 ,  \fraction -1 16 ) } 16 }
    \markup { (\fraction 1 4 , 0 ) } 4
    \grace {
      \markup { (\fraction 2 4 , \fraction "-1" 8 ) } 16
      \markup { (\fraction 2 4 , \fraction "-1" 16 ) } 16
    } 
    \markup { ( \fraction 2 4 , 0 ) }
  }
>>
@end lilypond


The placement of grace notes is synchronized between different staves.
In the following example, there are two sixteenth graces notes for
every eighth grace note

@lilypond[quote,raggedright,relative=2,verbatim,fragment] 
<< \new Staff { e4 \grace { c16[ d e f] } e4 }
   \new Staff { c4 \grace { g8[ b] } c4 } >>
@end lilypond



If you want to end a note with a grace, the standard trick is to put
the grace notes after a ``space note''

@lilypond[quote,raggedright,fragment,verbatim,relative=2]
\context Voice {
  << { d1^\trill_( }
     { s2 \grace { c16[ d] } } >>
  c4)
}
@end lilypond

@noindent
By adjusting the duration of the skip note (here it is a half-note),
the space between the main-note and the grace is adjusted.


A @code{\grace} section will introduce special typesetting settings,
for example, to produce smaller type, and set directions.  Hence, when
introducing layout tweaks, they should be inside the grace section,
for example,
@lilypond[quote,raggedright,fragment,verbatim,relative=2]
\new Voice {
  \acciaccatura {
    \stemDown
    f16->
    \stemNeutral
  }
  g4
}
@end lilypond

@noindent
The overrides should also be reverted inside the grace section.

The layout of grace sections can be changed throughout the music using
the function @code{add-grace-property}.  The following example
undefines the Stem direction for this grace, so stems do not always
point up.

@example
\new Staff @{
   #(add-grace-property 'Voice 'Stem 'direction '())
   @dots{}
@}
@end example

@noindent
Another option is to change the variables @code{startGraceMusic},
@code{stopGraceMusic}, @code{startAcciaccaturaMusic},
@code{stopAcciaccaturaMusic}, @code{startAppoggiaturaMusic},
@code{stopAppoggiaturaMusic}.  More information is in the file
@file{ly/@/grace@/-init@/.ly}.


@seealso

Program reference: @internalsref{GraceMusic}.

@refbugs

A score that starts with a @code{\grace} section needs an explicit
@code{\context Voice} declaration, otherwise the main note and grace
note end up on different staves.

Grace note synchronization can also lead to surprises.  Staff notation,
such as key signatures, bar lines, etc. are also synchronized.  Take
care when you mix staves with grace notes and staves without, for example,

@lilypond[quote,raggedright,relative=2,verbatim,fragment]
<< \new Staff { e4 \bar "|:" \grace c16 d4 }
   \new Staff { c4  \bar "|:"  d4 } >>
@end lilypond

@noindent
This can be remedied by inserting grace skips, for the above example

@example
\new Staff @{ c4  \bar "|:"  \grace s16 d4 @} 
@end example

Grace sections should only be used within sequential music
expressions.  Nesting or juxtaposing grace sections is not supported,
and might produce crashes or other errors.


@node Glissando
@subsection Glissando
@cindex Glissando 

@cindex @code{\glissando}

A glissando is a smooth change in pitch.  It is denoted by a line or a
wavy line between two notes.  It is requested by attaching 
@code{\glissando} to a note

@lilypond[quote,raggedright,fragment,relative=2,verbatim]
c\glissando c'
@end lilypond

@seealso

Program reference: @internalsref{Glissando}, and @internalsref{GlissandoEvent}.

Example files: @file{input/@/regression/@/glissando@/.ly}.

 

@refbugs

Printing text over the line (such as @emph{gliss.}) is not supported.


@node Dynamics
@subsection Dynamics
@cindex Dynamics



@cindex @code{\ppp}
@cindex @code{\pp}
@cindex @code{\p}
@cindex @code{\mp}
@cindex @code{\mf}
@cindex @code{\f}
@cindex @code{\ff}
@cindex @code{\fff}
@cindex @code{\ffff}
@cindex @code{\fp}
@cindex @code{\sf}
@cindex @code{\sff}
@cindex @code{\sp}
@cindex @code{\spp}
@cindex @code{\sfz}
@cindex @code{\rfz}


Absolute dynamic marks are specified using a command after a note
@code{c4\ff}.  The available dynamic marks are @code{\ppp},
@code{\pp}, @code{\p}, @code{\mp}, @code{\mf}, @code{\f}, @code{\ff},
@code{\fff}, @code{\fff}, @code{\fp}, @code{\sf}, @code{\sff},
@code{\sp}, @code{\spp}, @code{\sfz}, and @code{\rfz}

@lilypond[quote,verbatim,raggedright,fragment,relative=2]
  c\ppp c\pp c \p c\mp c\mf c\f c\ff c\fff
  c2\fp c\sf c\sff c\sp c\spp c\sfz c\rfz
@end lilypond

@cindex @code{\<}
@cindex @code{\>}
@cindex @code{\"!}



A crescendo mark is started with @code{\<} and terminated with
@code{\!}.  A decrescendo is started with @code{\>} and also terminated
with @code{\!}.  Because these marks are bound to notes, if you must
use spacer notes if multiple marks are needed during one note 

@lilypond[quote,raggedright,fragment,verbatim,relative=2]
  c\< c\! d\> e\! 
  << f1 { s4 s4\< s4\! \> s4\! } >>
@end lilypond
This may give rise to very short hairpins.  Use @code{minimum-length}
in @internalsref{Voice}.@internalsref{Hairpin} to lengthen them, for
example

@example
  \override Staff.Hairpin #'minimum-length = #5
@end example

You can also use a text saying @emph{cresc.} instead of hairpins.  Here
is an example how to do it

@lilypond[quote,raggedright,fragment,relative=2,verbatim]
  \setTextCresc
  c \< d e f\!
  \setHairpinCresc
  e\> d c b\!
@end lilypond

@cindex crescendo
@cindex decrescendo

You can also supply your own texts
@lilypond[quote,raggedright,fragment,relative=1,verbatim]
  \set crescendoText = \markup { \italic "cresc. poco" }
  \set crescendoSpanner = #'dashed-line
  a'2\< a a a\!\mf
@end lilypond

@cindex diminuendo


@refcommands

@cindex @code{\dynamicUp}
@code{\dynamicUp}, 
@cindex @code{\dynamicDown}
@code{\dynamicDown}, 
@cindex @code{\dynamicNeutral}
@code{\dynamicNeutral}.

@cindex direction, of dynamics

@seealso

Program reference: @internalsref{CrescendoEvent},
@internalsref{DecrescendoEvent}, and
@internalsref{AbsoluteDynamicEvent}.

Dynamics are @internalsref{DynamicText} and @internalsref{Hairpin}
objects.  Vertical positioning of these symbols is handled by the
@internalsref{DynamicLineSpanner} object.


@node Repeats
@section Repeats

Repetition is a central concept in music, and multiple notations exist
for repetitions.

@menu
* Repeat types::
* Repeat syntax::               
* Repeats and MIDI::            
* Manual repeat commands::      
* Tremolo repeats::             
* Tremolo subdivisions::        
* Measure repeats::             
@end menu

@node Repeat types
@subsection Repeat types

@cindex repeats
@cindex @code{\repeat}

The following types of repetition are supported

@table @code
@item unfold
Repeated music is fully written (played) out.  This is useful when
entering repetitious music.  This is the only kind of repeat that
is included in MIDI output.

@item volta
Repeats are not written out, but alternative endings (volte) are
printed, left to right with brackets.  This is the standard notation
for repeats with alternatives.  These are not played in MIDI output by default.

@ignore
@item fold
Alternative endings are written stacked.  This has limited use but may be
used to typeset two lines of lyrics in songs with repeats, see
@inputfileref{input,star-spangled-banner@/.ly}.
@end ignore

@c tremolo, beamed
@item tremolo
Make tremolo beams.  These are not played in MIDI output by default.

@item percent
Make beat or measure repeats.  These look like percent signs.  These are not played
in MIDI output by default.

@end table  

@node Repeat syntax
@subsection Repeat syntax


LilyPond has one syntactic construct for specifying different types of
repeats.  The syntax is

@example
  \repeat @var{variant} @var{repeatcount} @var{repeatbody}
@end example

If you have alternative endings, you may add
@cindex @code{\alternative}
@example
 \alternative @code{@{} @var{alternative1}
            @var{alternative2}
            @var{alternative3} @dots{} @code{@}}
@end example
where each @var{alternative} is a music expression.  If you do not
give enough alternatives for all of the repeats, the first alternative
is assumed to be played more than once.

Standard repeats are used like this
@lilypond[quote,raggedright,fragment,verbatim,relative=2]
c1
\repeat volta 2 { c4 d e f }
\repeat volta 2 { f e d c }
@end lilypond

With alternative endings
@lilypond[quote,raggedright,fragment,verbatim,relative=2]
c1
\repeat volta 2 {c4 d e f} 
\alternative { {d2 d} {f f,} }
@end lilypond


@lilypond[quote,raggedright,fragment,verbatim,relative=2]
\context Staff {
  \partial 4
  \repeat volta 4 { e | c2 d2 | e2 f2 | }
  \alternative { { g4 g g } { a | a a a a | b2. } }
}
@end lilypond

It is possible to shorten volta brackets
by setting @code{voltaSpannerDuration}.  In the next example, the
bracket only lasts one measure, which is a duration of 3/4. 



@lilypond[verbatim,raggedright,quote]
\relative c''{
    \time 3/4
    c c c 
    \set Staff.voltaSpannerDuration = #(ly:make-moment 3 4)
    \repeat "volta" 5 { d d d  }
    \alternative { { e e e f f f }
    { g g g } }
}
@end lilypond
        

@seealso

Examples:

Brackets for the repeat are normally only printed over the topmost
staff.  This can be adjusted by setting the @code{voltaOnThisStaff}
property @inputfileref{input/@/regression,volta@/-multi@/-staff@/.ly},
@inputfileref{input/@/regression,volta@/-chord@/-names@/.ly}


@refbugs

A nested repeat like

@example 
\repeat @dots{}
\repeat @dots{}
\alternative 
@end example 

@noindent
is ambiguous, since it is is not clear to which @code{\repeat} the
@code{\alternative} belongs.  This ambiguity is resolved by always
having the @code{\alternative} belong to the inner @code{\repeat}.
For clarity, it is advisable to use braces in such situations.
@cindex ambiguity



Timing information is not remembered at the start of an alternative,
so after a repeat timing information must be reset by hand, for
example by setting @code{Score.measurePosition} or entering
@code{\partial}.  Similarly, slurs or ties are also not repeated.




@node Repeats and MIDI
@subsection Repeats and MIDI

@cindex expanding repeats

With a little bit of tweaking, all types of repeats can be present
in the MIDI output.  This is achieved by applying the
@code{\unfoldrepeats} music function.  This functions changes all
repeats to unfold repeats.

@lilypond[verbatim,fragment,linewidth]
\unfoldrepeats {
  \repeat tremolo 8 {c'32 e' }
  \repeat percent 2 { c''8 d'' }
  \repeat volta 2 {c'4 d' e' f'} 
  \alternative {
    { g' a' a' g' }
    {f' e' d' c' }
  }
}
\bar "|."
@end lilypond

When creating a score file using @code{\unfoldrepeats} for midi, then
it is necessary to make two @code{\score} blocks.  One for MIDI (with
unfolded repeats) and one for notation (with volta, tremolo, and
percent repeats).  For example,

@example
  \score @{
      @var{..music..}
      \layout @{ .. @}
  @} 
  \score @{
      \unfoldrepeats @var{..music..}
      \midi @{ .. @}
  @} 
@end example

@node Manual repeat commands
@subsection Manual repeat commands

@cindex @code{repeatCommands}

The property @code{repeatCommands} can be used to control the layout of
repeats.  Its value is a Scheme list of repeat commands, where each repeat
command can be

@table @asis
@item @code{start-repeat},
  which prints a @code{|:} bar line;
@item @code{end-repeat},
  which prints a @code{:|} bar line;
@item @code{(volta @var{text})},
  which prints a volta bracket saying @var{text}: The text can be specified as
a text string or as a markup text, see @ref{Text markup}.  Do not
forget to change the font, as the default number font does not contain
alphabetic characters;
@item @code{(volta #f)}, which 
  stops a running volta bracket.
@end table

@lilypond[quote,raggedright,verbatim,fragment,relative=2]
c4
  \set Score.repeatCommands = #'((volta "93") end-repeat)
c4 c4
  \set Score.repeatCommands = #'((volta #f))
c4 c4
@end lilypond



@seealso

Program reference: @internalsref{VoltaBracket}, @internalsref{RepeatedMusic},
@internalsref{VoltaRepeatedMusic},
@internalsref{UnfoldedRepeatedMusic}, and
@internalsref{FoldedRepeatedMusic}.

@node Tremolo repeats
@subsection Tremolo repeats
@cindex tremolo beams

To place tremolo marks between notes, use @code{\repeat} with tremolo
style
@lilypond[quote,verbatim,raggedright]
\new Voice \relative c' {
  \repeat "tremolo" 8 { c16 d16 }
  \repeat "tremolo" 4 { c16 d16 }    
  \repeat "tremolo" 2 { c16 d16 }
}
@end lilypond

Tremolo marks can also be put on a single note.  In this case, the
note should not be surrounded by braces.
@lilypond[quote,verbatim,raggedright]
  \repeat "tremolo" 4 c'16
@end lilypond

Similar output is obtained using the tremolo subdivision, described in
@ref{Tremolo subdivisions}.

@seealso

In this manual: @ref{Tremolo subdivisions}, @ref{Repeats}.

Program reference: tremolo beams are @internalsref{Beam} objects.  Single stem
tremolos are @internalsref{StemTremolo} objects.  The music expression is
@internalsref{TremoloEvent}.

Example files: @inputfileref{input/@/regression,chord@/-tremolo@/.ly},
@inputfileref{input/@/regression,stem@/-tremolo@/.ly}.

@node Tremolo subdivisions
@subsection Tremolo subdivisions
@cindex tremolo marks
@cindex @code{tremoloFlags}

Tremolo marks can be printed on a single note by adding
`@code{:}[@var{number}]' after the note.  The number indicates the
duration of the subdivision, and it must be at least 8.  A
@var{length} value of 8 gives one line across the note stem.  If the
length is omitted, the last value (stored in @code{tremoloFlags}) is
used

@lilypond[quote,raggedright,verbatim,fragment]
  c'2:8 c':32 | c': c': |
@end lilypond

@c [TODO : stok is te kort bij 32en]
@c   somebody want to translate that into English?  :)

@refbugs

Tremolos entered in this way do not carry over into the MIDI output.

@seealso

In this manual: @ref{Tremolo repeats}.

Elsewhere: @internalsref{StemTremolo}, @internalsref{TremoloEvent}.

@node Measure repeats
@subsection Measure repeats

@cindex percent repeats
@cindex measure repeats

In the @code{percent} style, a note pattern can be repeated.  It is
printed once, and then the pattern is replaced with a special sign.
Patterns of one and two measures are replaced by percent-like signs,
patterns that divide the measure length are replaced by slashes

@lilypond[quote,verbatim,raggedright]
\new Voice \relative c' {
  \repeat "percent" 4  { c4 }
  \repeat "percent" 2 { c2 es2 f4 fis4 g4 c4 }
}
@end lilypond

@seealso

Program reference: @internalsref{RepeatSlash}, @internalsref{PercentRepeat},
@internalsref{PercentRepeatedMusic}, and
@internalsref{DoublePercentRepeat}.



@node Rhythmic music
@section Rhythmic music

Rhythmic music is primarily used for percussion and drum notation, but it can
also be used to show the rhythms of melodies.

@menu
* Showing melody rhythms::      
* Entering percussion::         
* Percussion staves::           
@end menu


@node Showing melody rhythms
@subsection Showing melody rhythms

Sometimes you might want to show only the rhythm of a melody.  This
can be done with the rhythmic staff.  All pitches of notes on such a
staff are squashed, and the staff itself has a single line

@lilypond[quote,raggedright,fragment,relative=1,verbatim]
\context RhythmicStaff {
  \time 4/4
  c4 e8 f g2 | r4 g r2 | g1:32 | r1 |
}
@end lilypond

@seealso

Program reference: @internalsref{RhythmicStaff}.

Examples: @inputfileref{input/@/regression,rhythmic@/-staff@/.ly}.


@node Entering percussion
@subsection Entering percussion

@cindex percussion
@cindex drums


Percussion notes may be entered in @code{\drummode} mode, which is
similar to the standard mode for entering notes.  Each piece of
percussion has a full name and an abbreviated name, and both can be used
in input files

@lilypond[quote,raggedright,verbatim]
\drums {
  hihat hh bassdrum bd
}
@end lilypond

The complete list of drum names is in the init file
@file{ly/@/drumpitch@/-init@/.ly}.
@c TODO: properly document this.

@seealso

Program reference: @internalsref{DrumNoteEvent}.

@node Percussion staves
@subsection Percussion staves
@cindex percussion
@cindex drums

A percussion part for more than one instrument typically uses a
multi line staff where each position in the staff refers to one piece
of percussion.


To typeset the music, the notes must be interpreted in a
@internalsref{DrumStaff} and @internalsref{DrumVoice} contexts

@c
@lilypond[quote,raggedright,verbatim]
up = \drummode { crashcymbal4 hihat8 halfopenhihat hh hh hh openhihat }
down = \drummode { bassdrum4 snare8 bd r bd sn4 }
  \new DrumStaff <<
    \new DrumVoice { \voiceOne \up } 
    \new DrumVoice { \voiceTwo \down } 
  >>
@end lilypond

The above example shows verbose polyphonic notation.  The short
polyphonic notation, described in @ref{Polyphony}, can also be used if
the @internalsref{DrumVoices} are instantiated by hand first.  For example, 

@lilypond[quote,raggedright,fragment,verbatim] 
\new DrumStaff <<
  \context DrumVoice = "1" {  s1 *2 }
  \context DrumVoice = "2" {  s1 *2 }
  \drummode {
    bd4 sn4 bd4 sn4
    <<
      { \repeat unfold 16 hh16 }
      \\
      { bd4 sn4 bd4 sn4 }
    >>
  }   
>>
@end lilypond


There are also other layout possibilities.  To use these, set the
property @code{drumStyleTable} in context @internalsref{DrumVoice}.
The following variables have been predefined

@table @code
@item drums-style
This is the default.  It typesets a typical drum kit on a five-line staff

@lilypond[quote,raggedright]
nam = \lyricmode { cymc cyms cymr hh hhc hho hhho hhp cb hc
    bd sn ss tomh tommh tomml toml tomfh tomfl }
mus = \drummode  { cymc cyms cymr hh | hhc hho hhho hhp | \break cb hc
    bd sn ss tomh tommh tomml toml tomfh tomfl s16 }
\score {
    << \new DrumStaff\with {
            \remove Bar_engraver
            \remove Time_signature_engraver
            \override Stem #'transparent = ##t
            \override Stem #'Y-extent-callback = ##f
            minimumVerticalExtent = #'(-4.0 . 5.0)
    } \mus
        \context Lyrics \nam 
    >>
    \layout {
    %% need to do this, because of indented @itemize
    linewidth= 9 \cm 
    \context { \Score
    \override LyricText #'font-family = #'typewriter
    \override BarNumber #'transparent =##T
}}}
@end lilypond

The drum scheme supports six different toms.  When there fewer toms, simply
select the toms that produce the desired result, i.e. to get toms on
the three middle lines you use @code{tommh}, @code{tomml} and
@code{tomfh}.

@item timbales-style
This typesets timbales on a two line staff

@lilypond[quote,raggedright]
nam = \lyricmode { timh ssh timl ssl cb }
mus = \drummode  { timh ssh timl ssl cb s16 }

<<
        \context DrumStaff \with {
            \remove Bar_engraver
            \remove Time_signature_engraver
            \override Stem #'transparent = ##t
            \override Stem #'Y-extent-callback = ##f
            \override StaffSymbol #'line-count = #2
            \override StaffSymbol #'staff-space = #2
            minimumVerticalExtent = #'(-3.0 . 4.0)
            drumStyleTable = #timbales-style
        } \mus
        \context Lyrics {
            \override LyricText #'font-family = #'typewriter

        \nam  }
>>
@end lilypond
@item congas-style
This typesets congas on a two line staff

@lilypond[quote,raggedright]
nam = \lyricmode { cgh cgho cghm ssh cgl cglo cglm ssl }
mus = \drummode  { cgh cgho cghm ssh cgl cglo cglm ssl s16 }
<<
        \context DrumStaff\with {
            \remove Bar_engraver
            \remove Time_signature_engraver
            drumStyleTable = #congas-style
            \override StaffSymbol #'line-count = #2
            
            %% this sucks; it will lengthen stems.
            \override StaffSymbol #'staff-space = #2
            \override Stem #'transparent = ##t
            \override Stem #'Y-extent-callback = ##f
        } \mus
        \context Lyrics {
                    \override LyricText #'font-family = #'typewriter
\nam  }
>>
@end lilypond
@item bongos-style
This typesets bongos on a two line staff

@lilypond[quote,raggedright]
nam = \lyricmode { boh boho bohm ssh bol bolo bolm ssl }
mus = \drummode  { boh boho bohm ssh bol bolo bolm ssl s16 }
<<
        \context DrumStaff\with {
            \remove Bar_engraver
            \remove Time_signature_engraver
            \override StaffSymbol #'line-count = #2
            drumStyleTable = #bongos-style
           
            %% this sucks; it will lengthen stems.
            \override StaffSymbol #'staff-space = #2
            \override Stem #'transparent = ##t
            \override Stem #'Y-extent-callback = ##f
        } \mus
        \context Lyrics {
                    \override LyricText #'font-family = #'typewriter
\nam  }
>>
@end lilypond

@item percussion-style
to typeset all kinds of simple percussion on one line staves
@lilypond[quote,raggedright]
nam = \lyricmode { tri trio trim gui guis guil cb cl tamb cab mar hc }
mus = \drummode  { tri trio trim gui guis guil cb cl tamb cab mar hc s16 }
<<
        \context DrumStaff\with{
            \remove Bar_engraver
            drumStyleTable = #percussion-style
            \override StaffSymbol #'line-count = #1
            \remove Time_signature_engraver
            \override Stem #'transparent = ##t
            \override Stem #'Y-extent-callback = ##f
        } \mus
        \context Lyrics {
          \override LyricText #'font-family = #'typewriter
          \nam
        }
>>
@end lilypond
@end table

If you do not like any of the predefined lists you can define your own
list at the top of your file

@lilypond[quote,raggedright,verbatim]
#(define mydrums '(
        (bassdrum     default   #f        -1)
        (snare        default   #f        0)
        (hihat        cross     #f        1)
        (pedalhihat   xcircle   "stopped" 2)
        (lowtom       diamond   #f       3)))
up = \drummode { hh8 hh hh hh hhp4 hhp }
down = \drummode { bd4 sn bd toml8 toml }

\new DrumStaff <<
    \set DrumStaff.drumStyleTable
       = #(alist->hash-table mydrums)
    \new DrumVoice { \voiceOne \up }
    \new DrumVoice { \voiceTwo \down }
>>
@end lilypond


@seealso

Init files: @file{ly/@/drumpitch@/-init@/.ly}.

Program reference: @internalsref{DrumStaff}, @internalsref{DrumVoice}.

@refbugs

Because general MIDI does not contain rim shots, the sidestick is used
for this purpose instead.

@node Piano music
@section Piano music

Piano staves are two normal staves coupled with a brace.  The staves
are largely independent, but sometimes voices can cross between the
two staves.  The same notation is also used for harps and other key
instruments.  The @internalsref{PianoStaff} is especially built to
handle this cross-staffing behavior.  In this section we discuss the
@internalsref{PianoStaff} and some other pianistic peculiarities.


@menu
* Automatic staff changes::     
* Manual staff switches::       
* Pedals::                      
* Arpeggio::                    
* Staff switch lines::          
* Cross staff stems::           
@end menu 

@refbugs

Dynamics are not centered, but workarounds do exist.  See the
``piano centered dynamics'' template in @ref{Piano templates}.

@cindex cross staff stem
@cindex stem, cross staff
@cindex distance between staves in piano music

The distance between the two staves is the same for all systems in the
score.  It is possible to override this per system, but it does require
an arcane command incantation.  See
@inputfileref{input/@/test,piano@/-staff@/-distance@/.ly}.


@node Automatic staff changes
@subsection Automatic staff changes
@cindex Automatic staff changes

Voices can be made to switch automatically between the top and the bottom
staff.  The syntax for this is

@quotation
@example
  \autochange @dots{}@var{music}@dots{} 
@end example
@end quotation

@noindent
This will create two staves inside the current PianoStaff, called
@code{up} and @code{down}.  The lower staff will be in bass clef by
default.

A @code{\relative} section that is outside of @code{\autochange} has
no effect on the pitches of @var{music}, so, if necessary, put
@code{\relative} inside @code{\autochange} like

@quotation
@example
\autochange \relative @dots{} @dots{}
@end example
@end quotation


The autochanger switches on basis of pitch (middle C is the turning
point), and it looks ahead skipping over rests to switch in
advance.  Here is a practical example
        
@lilypond[quote,verbatim,raggedright]
\context PianoStaff
  \autochange \relative c'
  {
    g4 a b c d r4 a g
  }
@end lilypond


@seealso

In this manual: @ref{Manual staff switches}.

Program reference: @internalsref{AutoChangeMusic}.



@refbugs

The staff switches may not end up in optimal places.  For high
quality output, staff switches should be specified manually.


@code{\autochange} cannot be inside @code{\times}. 

Internally, the @code{\partcombine} interprets both arguments as
@code{Voice}s named @code{one} and @code{two}, and then decides when
the parts can be combined.  Consequently, if the arguments switch to
differently named @internalsref{Voice} contexts, the events in those
will be ignored.


@node Manual staff switches
@subsection Manual staff switches

@cindex manual staff switches
@cindex staff switch, manual

Voices can be switched between staves manually, using the command
@example
\change Staff = @var{staffname} @var{music}
@end example

@noindent
The string @var{staffname} is the name of the staff.  It switches the
current voice from its current staff to the Staff called
@var{staffname}.  Typically @var{staffname} is @code{"up"} or
@code{"down"}.  The @context{Staff} referred to must already exist, so
usually the setup for a score will start with a setup of the staves,

@example
<<
  \context Staff = up @{
    \skip 1 * 10  %@emph{ keep staff alive}
    @}
  \context Staff = down @{
    \skip 1 * 10  %@emph{idem}
    @}
>>
@end example 


and the @context{Voice} is inserted afterwards

@example
\context Staff = down
  \new Voice @{ @dots{} \change Staff = up @dots{} @}
@end example


@node Pedals
@subsection Pedals
@cindex Pedals

Pianos have pedals that alter the way sound is produced.  Generally, a
piano has three pedals, sustain, una corda, and sostenuto.


Piano pedal instruction can be expressed by attaching
@code{\sustainDown}, @code{\sustainUp}, @code{\unaCorda},
@code{\treCorde}, @code{\sostenutoDown} and @code{\sostenutoUp} to a
note or chord

@lilypond[quote,raggedright,fragment,verbatim]
  c'4\sustainDown c'4\sustainUp
@end lilypond

What is printed can be modified by setting @code{pedal@var{X}Strings},
where @var{X} is one of the pedal types: @code{Sustain},
@code{Sostenuto} or @code{UnaCorda}.  Refer to
@internalsref{SustainPedal} in the program reference for more
information.

Pedals can also be indicated by a sequence of brackets, by setting the
@code{pedalSustainStyle} property to bracket objects

@lilypond[quote,raggedright,fragment,verbatim,relative=2]
  \set Staff.pedalSustainStyle = #'bracket
  c\sustainDown d e
  b\sustainUp\sustainDown
  b g \sustainUp a \sustainDown \bar "|."
@end lilypond

A third style of pedal notation is a mixture of text and brackets,
obtained by setting the @code{pedalSustainStyle} style property to
@code{mixed}

@lilypond[quote,raggedright,fragment,verbatim,relative=2]
  \set Staff.pedalSustainStyle = #'mixed
  c\sustainDown d e
  b\sustainUp\sustainDown
  b g \sustainUp a \sustainDown \bar "|."
@end lilypond

The default `*Ped.' style for sustain and damper pedals corresponds to
style @code{#'text}.  The sostenuto pedal uses @code{mixed} style by
default.

@lilypond[quote,raggedright,fragment,verbatim,relative=2]
  c\sostenutoDown d e c, f g a\sostenutoUp
@end lilypond

For fine-tuning of the appearance of a pedal bracket, the properties
@code{edge-width}, @code{edge-height}, and @code{shorten-pair} of
@code{PianoPedalBracket} objects (see
@internalsref{PianoPedalBracket} in the Program reference) can be modified.  For example, the
bracket may be extended to the right edge of the note head

@lilypond[quote,raggedright,fragment,verbatim,relative=2]
  \override Staff.PianoPedalBracket #'shorten-pair = #'(0 . -1.0)
  c\sostenutoDown d e c, f g a\sostenutoUp
@end lilypond

@node Arpeggio
@subsection Arpeggio
@cindex Arpeggio

@cindex broken arpeggio
@cindex @code{\arpeggio}

You can specify an arpeggio sign on a chord by attaching an
@code{\arpeggio} to a chord


@lilypond[quote,raggedright,fragment,relative=1,verbatim]
  <c e g c>\arpeggio
@end lilypond

When an arpeggio crosses staves, you attach an arpeggio to the chords
in both staves, and set
@internalsref{PianoStaff}.@code{connectArpeggios}

@lilypond[quote,raggedright,fragment,relative=1,verbatim]
\context PianoStaff <<
  \set PianoStaff.connectArpeggios = ##t
  \new Staff  { <c' e g c>\arpeggio }
  \new Staff { \clef bass  <c,, e g>\arpeggio }
>>
@end lilypond

The direction of the arpeggio is sometimes denoted by adding an
arrowhead to the wiggly line

@lilypond[quote,raggedright,fragment,relative=1,verbatim]
\context Voice {
  \arpeggioUp
  <c e g c>\arpeggio
  \arpeggioDown
  <c e g c>\arpeggio
}
@end lilypond

A square bracket on the left indicates that the player should not
arpeggiate the chord

@c todo: ugh, lousy typography.  Look for real example. --hwn

@lilypond[quote,raggedright,fragment,relative=1,verbatim]
  \arpeggioBracket
  <c' e g c>\arpeggio
@end lilypond

@refcommands

@cindex @code{\arpeggio}
@code{\arpeggio},
@cindex @code{\arpeggioUp}
@code{\arpeggioUp},
@cindex @code{\arpeggioDown}
@code{\arpeggioDown},
@cindex @code{\arpeggioNeutral}
@code{\arpeggioNeutral},
@cindex @code{\arpeggioBracket}
@code{\arpeggioBracket}.

@seealso

Program reference: @internalsref{ArpeggioEvent},
@internalsref{Arpeggio}.

@refbugs

It is not possible to mix connected arpeggios and unconnected
arpeggios in one @internalsref{PianoStaff} at the same point in time.

@node Staff switch lines
@subsection Staff switch lines


@cindex follow voice
@cindex staff switching
@cindex cross staff

@cindex @code{followVoice}

Whenever a voice switches to another staff a line connecting the notes
can be printed automatically.  This is switched on by setting
@code{PianoStaff.followVoice} to true

@lilypond[quote,raggedright,fragment,relative=1,verbatim]
\context PianoStaff <<
  \set PianoStaff.followVoice = ##t
  \context Staff \context Voice {
    c1
    \change Staff=two
    b2 a
  }
 \context Staff=two { \clef bass \skip 1*2 }
>>  
@end lilypond

@seealso

Program reference: @internalsref{VoiceFollower}.

@refcommands

@cindex @code{\showStaffSwitch}
@code{\showStaffSwitch}, 
@cindex @code{\hideStaffSwitch}
@code{\hideStaffSwitch}.


@node Cross staff stems
@subsection Cross staff stems

The chords which cross staves may be produced by increasing the length
of the stem in the lower stave, so it reaches the stem in the upper
stave, or vice versa.

@lilypond[raggedright,verbatim,quote]
stemExtend = \once \override Stem #'length = #22
noFlag = \once \override Stem #'flag-style = #'no-flag
\context PianoStaff <<
  \new Staff {
    \stemDown \stemExtend
    f'4
    \stemExtend \noFlag
    f'8
  }
  \new Staff {
    \clef bass
    a4 a8
  }
>>
@end lilypond


@node Vocal music
@section Vocal music

There are three different issues when printing vocal music

@itemize @bullet
@item
  Song texts must be entered as texts, not notes.  For example, the
input @code{d} should be interpreted as a one letter syllable, not the note D.
@item
  Song texts must be printed as text, not as notes. 
@item
  Song texts must be aligned with the notes of their melody
@end itemize

The simplest solution to printing music uses the @code{\addlyrics}
function to solve all these problems at once.  However, these
three functions can be controlled separately, which is necessary
for complex vocal music. 


@menu
* Setting simple songs::        
* Entering lyrics::             
* Hyphens and extenders::       
* The Lyrics context::          
* Flexibility in alignment::    
* More stanzas::                
* Ambitus::                     
@end menu

@node Setting simple songs
@subsection Setting simple songs

The easiest way to add lyrics to a melody is to append
@cindex \addlyrics
@example
  \addlyrics @{ @var{the lyrics} @} 
@end example

@noindent
to a melody.  Here is an example,

@lilypond[raggedright,verbatim,fragment,quote]
  \time 3/4 
  \relative { c2 e4 g2. }
  \addlyrics { play the game }
@end lilypond

More stanzas can be added by adding more
@code{\addlyrics} sections 

@lilypond[raggedright,verbatim,fragment,quote]
  \time 3/4
  \relative { c2 e4 g2. }
  \addlyrics { play the game } 
  \addlyrics { speel het spel } 
  \addlyrics { joue le jeu }
@end lilypond

@c TODO - this isn't such a great place for this note, but I can't
@c  find a better place without rearranging a lot of lyric stuff.
@c  It's yet another thing to look at post-3.0.

The @code{\addlyrics} command is actually just a convienient way
to write a more complicated LilyPond structure that sets up the
lyrics.  You should use @code{\addlyrics} unless you need to
fancy things, in which case you should investigate
@code{\lyricsto} or @code{\lyricmode}.

@example
  @{ MUSIC @}
  \addlyrics @{ LYRICS @}
@end example

is the same as

@example
  \context Voice = blah @{ music @}
  \lyricsto "blah" \lyricsmode \new lyrics @{ LYRICS @}
@end example


@node Entering lyrics
@subsection Entering lyrics


@cindex lyrics
@cindex @code{\lyricmode}
@cindex punctuation

Lyrics are entered in a special input mode.  This mode is is introduced
by the keyword @code{\lyricmode}, or by using @code{addlyrics} or
@code{lyricsto}.  In this mode you can enter lyrics,
with punctuation and accents, and the input @code{d} is not parsed as
a pitch, but rather as a one letter syllable.  Syllables are entered
like notes, but with pitches replaced by text.  For example,
@example
  \lyricmode @{ Twin-4 kle4 twin- kle litt- le star2 @}
@end example


A word lyrics mode begins with an alphabetic character, and ends with
any space or digit.  The following characters can be any character
that is not a digit or white space.  One important consequence of this
is that a word can end with @code{@}}.  The following example is
usually a mistake in the input file.  The syllable includes a @code{@}}, so the
opening brace is not balanced
@example
  \lyricmode @{ twinkle@}
@end example

@cindex @code{\property}, in @code{\lyricmode}
@noindent
Similarly, a period which follows an alphabetic sequence is included in
the resulting string.  As a consequence, spaces must be inserted around
property commands
@example
  \override Score . LyricText #'font-shape = #'italic
@end example

@cindex @code{_}
@cindex spaces, in lyrics
@cindex quotes, in lyrics

Any @code{_} character which appears in an unquoted word is converted
to a space.  This provides a mechanism for introducing spaces into words
without using quotes.  Quoted words can also be used in Lyrics mode to
specify words that cannot be written with the above rules.  The
following example incorporates double quotes

@example
  \lyricmode @{ He said: "\"Let" my peo ple "go\"" @}
@end example

This example is slightly academic, since it gives better looking
results to use single quotes, @code{``} and @code{''}
@example
  \lyricmode @{ He said: ``Let my peo ple go'' @}
@end example


The full definition of a word start in Lyrics mode is somewhat more
complex.

A word in Lyrics mode begins with: an alphabetic character, @code{_},
@code{?}, @code{!}, @code{:}, @code{'}, the control characters @code{^A}
through @code{^F}, @code{^Q} through @code{^W}, @code{^Y}, @code{^^},
any 8-bit character with ASCII code over 127, or a two-character
combination of a backslash followed by one of @code{`}, @code{'},
@code{"}, or @code{^}.



@seealso

Program reference: events @internalsref{LyricEvent}, and
@internalsref{LyricText}.

@refbugs

The definition of lyrics mode is too complex.

@node Hyphens and extenders
@subsection Hyphens and extenders

@cindex hyphens

Centered hyphens are entered as `@code{-}@code{-}' between syllables.
The hyphen will have variable length depending on the space between
the syllables and it will be centered between the syllables.

@cindex melisma
@cindex extender

When a lyric is sung over many notes (this is called a melisma), this is
indicated with a horizontal line centered between a syllable and the
next one.  Such a line is called an extender line, and it is entered as
@code{__}.


@seealso

Program reference: @internalsref{HyphenEvent}, 
@internalsref{ExtenderEvent}, @internalsref{LyricHyphen}, and
@internalsref{LyricExtender}

Examples: @inputfileref{input/@/test,lyric@/-hyphen@/-retain@/.ly}.



@node The Lyrics context
@subsection  The Lyrics context


Lyrics are printed by interpreting them in a @internalsref{Lyrics} context
@example
  \context Lyrics \lyricmode @dots{}
@end example

@cindex automatic syllable durations
@cindex @code{\lyricsto}
@cindex lyrics and melodies

This will place the lyrics according to the durations that were
entered.  The lyrics can also be aligned under a given melody
automatically.  In this case, it is no longer necessary to enter the
correct duration for each syllable.  This is achieved by combining the
melody and the lyrics with the @code{\lyricsto} expression
@example
\lyricsto @var{name} \new Lyrics @dots{} 
@end example

This aligns the lyrics to the
@c
notes of the @internalsref{Voice} context called @var{name}, which has
to exist.  Therefore, normally the @code{Voice} is specified first, and
then the lyrics are specified with @code{\lyricsto}.  The command
@code{\lyricsto} switches to @code{\lyricmode} mode automatically, so the
@code{\lyricmode} keyword may be omitted.

For different or more complex orderings, the best way is to setup the
hierarchy of staves and lyrics first, e.g.
@example
\context ChoirStaff  <<
  \context Lyrics = sopranoLyrics @{ s1 @}
  \context Voice = soprano @{ @emph{music} @}
  \context Lyrics = tenorLyrics @{ s1 @}
  \context Voice = tenor @{ @emph{music} @}
>>
@end example
and then combine the appropriate melodies and lyric lines
@example
  \lyricsto "soprano" \context Lyrics = sopranoLyrics
    @emph{the lyrics}
@end example

@noindent
The final input would resemble

@example
<<\context ChoirStaff  << @emph{setup the music}  >>
  \lyricsto "soprano" @emph{etc}
  \lyricsto "alto" @emph{etc}
  @emph{etc}
>>
@end example 


The @code{\lyricsto} command detects melismata: it only puts one
syllable under a tied or slurred group of notes.  If you want to force
an unslurred group of notes to be a melisma, insert @code{\melisma}
after the first note of the group, and @code{\melismaEnd} after the
last one, e.g.

@lilypond[quote,relative=2,raggedright,fragment,verbatim]
<<
  \context Voice = "lala" {
    \time 3/4
    f4 g8
    \melisma 
    f e f
    \melismaEnd
    e2
  }
  \lyricsto "lala" \new Lyrics {
    la di __ daah 
  }
>>
@end lilypond

In addition, notes are considered a melisma if they are manually
beamed, and automatic beaming (see @ref{Setting automatic beam
behavior}) is switched off.

@ignore

@c nonformation:

The criteria for deciding melismata can
be tuned with the property @code{melismaBusyProperties}.  See
@internalsref{Melisma_translator} in the program reference for more
information.

@end ignore

Lyrics can also be entered without @code{\lyricsto}.  In this case the
durations of each syllable must be entered explicitly, for example,

@verbatim
  play2 the4 game2.
  sink2 or4 swim2.  
@end verbatim

The alignment to a melody can be specified with the
@code{associatedVoice} property,

@verbatim
  \set associatedVoice = #"lala"
@end verbatim 

@noindent
The value of the property (here: @code{"lala"}) should be the name of
a @internalsref{Voice} context.  Without this setting, extender lines
will not be formatted properly.

Here is an example demonstrating manual lyric durations,

@lilypond[relative=1,raggedright,verbatim,fragment,quote]
<< \context Voice = melody {
     \time 3/4
     c2 e4 g2.
  } 
  \new Lyrics \lyricmode {
    \set associatedVoice = #"melody"
    play2 the4 game2.
  } >>
@end lilypond

@cindex SATB
@cindex choral score

A complete example of a SATB score setup is in section
@ref{Small ensembles}.


@refcommands

@code{\melisma}, @code{\melismaEnd}
@cindex @code{\melismaEnd}
@cindex @code{\melisma}

@seealso

Program reference: @internalsref{LyricCombineMusic},
@internalsref{Lyrics}, @internalsref{Melisma_translator}.

Examples: @ref{Small ensembles},
@inputfileref{input/@/regression,lyric@/-combine@/-new@/.ly},
@c TODO: make separate section for melismata 
@inputfileref{input/@/test,lyrics@/-melisma@/-variants@/.ly}.
@inputfileref{input/@/test,lyrics@/-melisma@/-faster@/.ly}.
 
@refbugs

Melismata are not detected automatically, and extender lines must be
inserted by hand.


@c TODO: document \new Staff << Voice \lyricsto >> bug

@node Flexibility in alignment
@subsection Flexibility in alignment


Often, different stanzas of one song are put to one melody in slightly
differing ways.  Such variations can still be captured with
@code{\lyricsto}.

One possibility is that the text has a melisma in one stanza, but
multiple syllables in another one.  One solution is to make the faster
voice ignore the melisma.  This is done by setting
@code{ignoreMelismata} in the Lyrics context.

There has one tricky aspect.  The setting for @code{ignoreMelismata}
must be set one syllable @emph{before} the non-melismatic syllable
in the text, as shown here,

@lilypond[verbatim,raggedright,quote]
<<
  \relative \context Voice = "lahlah" {
    \set Staff.autoBeaming = ##f 
    c4
    \slurDotted
    f8.[( g16])
    a4
  }
  \new Lyrics \lyricsto "lahlah" {
    more slow -- ly
  }
  \new Lyrics \lyricsto "lahlah" {
    \set ignoreMelismata = ##t % applies to "fas"
    go fas -- ter
    \unset ignoreMelismata
    still
  }
>>
@end lilypond


The @code{ignoreMelismata} applies to the syllable ``fas'', so it
should be entered before ``go''.

The reverse is also possible: making a lyric line slower than the
standard.  This can be achieved by insert @code{\skip}s into the
lyrics.  For every @code{\skip}, the text will be delayed another note.
For example,

@lilypond[verbatim,raggedright,quote]
\relative { c c g' }
\addlyrics {
  twin -- \skip 4
  kle
}
@end lilypond

More complex variations in text underlay are possible.  It is possible
to switch the melody for a line of lyrics during the text.  This is
done by setting the @code{associatedVoice} property.  In the example 

@lilypond[raggedright,quote]

<<
  \relative \context Voice = "lahlah" {
    \set Staff.autoBeaming = ##f 
    c4
    <<
      \context Voice = alternative {
        \voiceOne
        \times 2/3 {
          % show associations clearly.
          \override NoteColumn #'force-hshift = #-3
          f8 f g
        }
      }
      {
        \voiceTwo
        f8.[ g16]
        \oneVoice
      } >>
    a8( b) c
  }
  \new Lyrics \lyricsto "lahlah" {
    Ju -- ras -- sic Park
  }
  \new Lyrics \lyricsto "lahlah" {
    % Tricky: need to set associatedVoice
    % one syllable too soon! 
    \set associatedVoice = alternative % applies to "ran"
    Ty --
    ran  --
    no --
    \set associatedVoice = lahlah % applies to "rus"
    sau -- rus Rex
  } >>
@end lilypond

@noindent
the text for the first stanza is set to a melody called ``lahlah'',

@verbatim
\new Lyrics \lyricsto "lahlah" {
  Ju -- ras -- sic Park
}
@end verbatim 


The second stanza initially is set to the @code{lahlah} context, but
for the syllable ``ran'', it switches to a different melody.
This is achieved with
@example
  \set associatedVoice = alternative
@end example

@noindent
Here, @code{alternative} is the name of the @code{Voice} context
containing the triplet.

Again, the command must be one syllable too early, before ``Ty'' in
this case.

@verbatim
\new Lyrics \lyricsto "lahlah" {
  \set associatedVoice = alternative % applies to "ran"
  Ty --
  ran  --
  no --
  \set associatedVoice = lahlah % applies to "rus"
  sau -- rus Rex
}
@end verbatim 

@noindent
The underlay is switched back to the starting situation by assigning
@code{lahlah} to @code{associatedVoice}.




@node More stanzas
@subsection More stanzas

@cindex phrasing, in lyrics


@cindex stanza number
@cindex singer's names
@cindex name of singer 

Stanza numbers can be added by setting @code{stanza}, e.g.

@lilypond[quote,raggedright,verbatim,relative=2,fragment]
\new Voice {
  \time 3/4 g2 e4 a2 f4 g2.
} \addlyrics {
  \set stanza = "1. "
  Hi, my name is Bert.
} \addlyrics {
  \set stanza = "2. "
  Oh, che -- ri, je t'aime
}
@end lilypond

These numbers are put just before the start of first syllable.

Names of singers can also be added.  They are printed at the start of
the line, just like instrument names.  They are created by setting
@code{vocalName}.  A short version may be entered as @code{vocNam}.


@lilypond[fragment,raggedright,quote,verbatim,relative=2]
\new Voice {
  \time 3/4 g2 e4 a2 f4 g2.
} \addlyrics {
  \set vocalName = "Bert "
  Hi, my name is Bert.
} \addlyrics {
  \set vocalName = "Ernie "
  Oh, che -- ri, je t'aime
}
@end lilypond

@seealso

Program reference: Layout objects @internalsref{LyricText} and
@internalsref{VocalName}.  Music expressions
@internalsref{LyricEvent}.



@node Ambitus
@subsection Ambitus
@cindex ambitus

The term @emph{ambitus} denotes a range of pitches for a given voice
in a part of music.  It also may denote the pitch range that a musical
instrument is capable of playing.  Ambits are printed on vocal parts,
so performers can easily determine it meets their capabilities.

It denoted at the beginning of a piece near the initial clef.  The
range is graphically specified by two note heads, that represent the
minimum and maximum pitch.  To print such ambits, add the
@internalsref{Ambitus_engraver} to the @internalsref{Voice} context,
for example,

@example
  \layout @{
    \context @{
      \Voice
      \consists Ambitus_engraver
    @}
  @}
@end example

This results in the following output

@lilypond[quote,raggedright]
\layout {
  \context {
    \Staff
    \consists Ambitus_engraver
  }
}

\relative \new Staff {
  as'' c e2 cis,2
}
@end lilypond

If you have multiple voices in a single staff, and you want a single
ambitus per staff rather than per each voice, add the
@internalsref{Ambitus_engraver} to the @internalsref{Staff} context
rather than to the @internalsref{Voice} context.  Here is an example,

@lilypond[verbatim,raggedright,quote]
\new Staff <<
  \new Voice \with {
    \consists "Ambitus_engraver"
  } \relative c'' {
    \override Ambitus #'X-offset-callbacks
      = #(list (lambda (grob axis) -1.0))
    \voiceOne
    c4 a d e f2
  }
  \new Voice \with {
    \consists "Ambitus_engraver"
  } \relative c' {
    \voiceTwo
    es4 f g as b2
  }
>>
@end lilypond

@noindent
This example uses one advanced feature,

@example
  \override Ambitus #'X-offset-callbacks
    = #(list (lambda (grob axis) -1.0))
@end example

@noindent
This code moves the ambitus to the left.  The same effect could have
been achieved with @code{extra-offset}, but then the formatting system
would not reserve space for the moved object. 

@seealso

Program reference: @internalsref{Ambitus},
@internalsref{AmbitusLine}, @internalsref{AmbitusNoteHead},
@internalsref{AmbitusAccidental}.

Examples:  @inputfileref{input/@/regression,ambitus@/.ly}.

@refbugs

There is no collision handling in the case of multiple per-voice
ambitus.

@node Other instrument specific notation, Tablatures, Vocal music, Notation manual
@section Other instrument specific notation

This section includes extra information for writing string music, and may
include extra information for other instruments in the future.

@menu
* Harmonic notes::              
@end menu

@node Harmonic notes,  , Other instrument specific notation, Other instrument specific notation
@subsection Harmonic notes

@cindex artificial harmonics
@cindex harmonics

Artificial harmonics are notated with a different notehead style.  They
are entered by 
marking the harmonic pitch with @code{\harmonic}.

@lilypond[raggedright,verbatim,quote,fragment]
 <c' g'\harmonic>4
@end lilypond


@node Tablatures, Popular music, Other instrument specific notation, Notation manual
@section Tablatures

@cindex tablature
@cindex guitar tablature

Tablature notation is used for notating music for plucked string
instruments.  Pitches are not denoted with note heads, but by
indicating on which string and fret a note must be played.  LilyPond
offers limited support for tablature.

@menu
* Tablatures basic::            
* Non-guitar tablatures::       
@end menu

@node Tablatures basic, Non-guitar tablatures, Tablatures, Tablatures
@subsection Tablatures basic
@cindex Tablatures basic

The string number associated to a note is given as a backslash
followed by a number, e.g. @code{c4\3} for a C quarter on the third
string.  By default, string 1 is the highest one, and the tuning
defaults to the standard guitar tuning (with 6 strings).  The notes
are printed as tablature, by using @internalsref{TabStaff} and
@internalsref{TabVoice} contexts

@lilypond[quote,raggedright,fragment,verbatim]
 \context TabStaff {
  a,4\5 c'\2 a\3 e'\1
  e\4 c'\2 a\3 e'\1
}
@end lilypond

@cindex @code{minimumFret}
@cindex fret

When no string is specified, the first string that does not give a
fret number less than @code{minimumFret} is selected.  The default
value for @code{minimumFret} is 0


@example
e16 fis gis a b4
\set TabStaff.minimumFret = #8
e16 fis gis a b4
@end example
@lilypond[quote,raggedright]
frag =  {
  \key e \major
  e16 fis gis a b4
  \set TabStaff.minimumFret = #8
  e16 fis gis a b4
}
  \context StaffGroup <<
    \context Staff { \clef "G_8" \frag }
    \context TabStaff { \frag }
  >>
@end lilypond

@seealso

Program reference: @internalsref{TabStaff}, @internalsref{TabVoice}, and
@internalsref{StringNumberEvent}.

@refbugs

Chords are not handled in a special way, and hence the automatic
string selector may easily select the same string to two notes in a
chord.


@node Non-guitar tablatures,  , Tablatures basic, Tablatures
@subsection Non-guitar tablatures
@cindex Non-guitar tablatures

You can change the number of strings, by setting the number of lines
in the @internalsref{TabStaff}. 

You can change the tuning of the strings.  A string tuning is given as
a Scheme list with one integer number for each string, the number
being the pitch (measured in semitones relative to middle C) of an
open string.  The numbers specified for @code{stringTuning} are the
numbers of semitones to subtract or add, starting the specified pitch
by default middle C, in string order.  In the next example,
@code{stringTunings} is set for the pitches e, a, d, and g

@lilypond[quote,raggedright,fragment,verbatim]
  \context TabStaff <<
    \set TabStaff.stringTunings = #'(-5 -10 -15 -20)
    
     {
      a,4 c' a e' e c' a e'
    }
  >> 
@end lilypond

@refbugs

No guitar special effects have been implemented.

@seealso

Program reference: @internalsref{Tab_note_heads_engraver}.


@node Popular music, Orchestral music, Tablatures, Notation manual
@section Popular music 

This section discusses issues that arise when writing popular music.

@menu
* Chord names::                 
* Chords mode::                 
* Printing chord names::        
* Fret diagrams::               
* Improvisation::               
@end menu

@node Chord names, Chords mode, Popular music, Popular music
@subsection Chord names
@cindex Chords

LilyPond has support for printing chord names.  Chords may be entered
in musical chord notation, i.e. @code{< .. >}, but they can also be
entered by name.  Internally, the chords are represented as a set of
pitches, so they can be transposed


@lilypond[quote,raggedright,verbatim,raggedright]
twoWays = \transpose c c' {
  \chordmode {
    c1 f:sus4 bes/f
  }
  <c e g>
  <f bes c'>
  <f bes d'>
}

<< \context ChordNames \twoWays
   \context Voice \twoWays >> 
@end lilypond

This example also shows that the chord printing routines do not try to
be intelligent.  The last chord (@code{f bes d}) is not interpreted as
an inversion.

@c this menu isn't needed.
@ignore
@menu
* Chords mode::                 
* Printing chord names::        
@end menu
@end ignore

@node Chords mode
@subsection Chords mode
@cindex Chords mode

In chord mode sets of pitches (chords) are entered with normal note
names.  A chord is entered by the root, which is entered like a
normal pitch

@lilypond[quote,raggedright,fragment,verbatim]
  \chordmode { es4. d8 c2 }
@end lilypond

@noindent
The mode is introduced by the keyword @code{\chordmode}.

@cindex chord entry
@cindex chord mode

Other chords may be entered by suffixing a colon and introducing a
modifier (which may include a number if desired)
@c
@lilypond[quote,fragment,verbatim]
  \chordmode { e1:m e1:7 e1:m7  }
@end lilypond
The first number following the root is taken to be the `type' of the
chord, thirds are added to the root until it reaches the specified
number
@lilypond[quote,fragment,verbatim]
  \chordmode { c:3 c:5 c:6 c:7 c:8 c:9 c:10 c:11 }
@end lilypond

@cindex root of chord
@cindex additions, in chords
@cindex removals, in chords

More complex chords may also be constructed adding separate steps
to a chord.  Additions are added after the number following
the colon, and are separated by dots
@c
@lilypond[quote,verbatim,fragment]
  \chordmode { c:5.6 c:3.7.8 c:3.6.13 }
@end lilypond
Chord steps can be altered by suffixing a @code{-} or @code{+} sign
to the number
@lilypond[quote,verbatim,fragment]
  \chordmode { c:7+ c:5+.3-  c:3-.5-.7- }
@end lilypond
Removals are specified similarly, and are introduced by a caret.  They
must come after the additions
@lilypond[quote,verbatim,fragment]
  \chordmode { c^3 c:7^5 c:9^3.5 }
@end lilypond

Modifiers can be used to change pitches.  The following modifiers are
supported
@table @code
@item m
  is the minor chord.  This modifier lowers the 3rd and (if present) the 7th step.
@item dim
  is the diminished chord.  This modifier lowers the 3rd, 5th and (if present)
  the 7th step.
@item aug
  is the augmented chord.  This modifier raises the 5th step.
@item maj
  is the major 7th chord.  This modifier raises the 7th step if present.  
@item sus
  is the suspended 4th or 2nd.  This modifier removes the 3rd
step.  Append either @code{2} or @code{4} to add the 2nd or 4th step to
the chord.
@end table
Modifiers can be mixed with additions
@lilypond[quote,verbatim,fragment]
  \chordmode { c:sus4 c:7sus4 c:dim7 c:m6 } 
@end lilypond

@cindex modifiers, in chords. 
@cindex @code{aug}
@cindex @code{dim}
@cindex @code{maj}
@cindex @code{sus}
@cindex @code{m}

Since an unaltered 11 does not sound good when combined with an
unaltered 3, the 11 is removed in this case (unless it is added
explicitly)
@c
@lilypond[quote,raggedright,fragment,verbatim]
  \chordmode { c:13 c:13.11 c:m13 }
@end lilypond

@cindex @code{/}

An inversion (putting one pitch of the chord on the bottom), as well
as bass notes, can be specified by appending
@code{/}@var{pitch} to the chord
@lilypond[quote,raggedright,fragment,verbatim]
  \chordmode { c1 c/g c/f }
@end lilypond
@cindex @code{/+}

A bass note can be added instead of transposed out of the chord,
by using  @code{/+}@var{pitch}.

@lilypond[quote,raggedright,fragment,verbatim]
\chordmode { c1 c/+g c/+f }
@end lilypond

Chords is a mode similar to @code{\lyricmode} etc.  Most
of the commands continue to work, for example, @code{r} and
@code{\skip} can be used to insert rests and spaces, and property
commands may be used to change various settings.



@refbugs

Each step can only be present in a chord once.  The following
simply produces the augmented chord, since @code{5+} is interpreted
last
@cindex clusters
@lilypond[quote,raggedright,verbatim,fragment]
\chordmode { c:5.5-.5+ }
@end lilypond


@node Printing chord names
@subsection Printing chord names

@cindex printing chord names
@cindex chord names
@cindex chords

For displaying printed chord names, use the @internalsref{ChordNames} context.
The chords may be entered either using the notation
described above, or directly using @code{<} and @code{>}

@lilypond[quote,verbatim,raggedright]
harmonies = {
  \chordmode {a1 b c} <d' f' a'>  <e' g' b'>
}
<<
  \context ChordNames \harmonies
  \context Staff \harmonies
>>
@end lilypond

You can make the chord changes stand out by setting
@internalsref{ChordNames}.@code{chordChanges} to true.  This will only
display chord names when there is a change in the chords scheme and at
the start of a new line

@c  originally this had linewidth=9\cm, but I though that raggedright would be better
@lilypond[quote,verbatim,raggedright]
harmonies = \chordmode {
  c1:m c:m \break c:m c:m d
}
<<
  \context ChordNames {
    \set chordChanges = ##t
    \harmonies }
  \context Staff \transpose c c' \harmonies
>>
@end lilypond

The previous examples all show chords over a staff.  This is not
necessary.  Chords may also be printed separately.  It may be necessary
to add @internalsref{Volta_engraver} and @internalsref{Bar_engraver}
for showing repeats.

@lilypond[raggedright,verbatim]
\new ChordNames \with {
  \override BarLine #'bar-size = #4
  voltaOnThisStaff = ##t
  \consists Bar_engraver
  \consists "Volta_engraver"
} 
\repeat volta 2 \chordmode {
  f1:maj f:7 bes:7
  c:maj  
} \alternative {
  es e
}
@end lilypond


The default chord name layout is a system for Jazz music, proposed by
Klaus Ignatzek (see @ref{Literature list}).  It can be tuned through the
following properties

@table @code
@cindex @code{chordNameExceptions}
@item chordNameExceptions
This is a list that contains the chords that have special formatting.

The exceptions list should be encoded as encoded as
@verbatim
        @{ <c f g bes>1 \markup @{ \\super \"7\" \"wahh\" @} @}
@end verbatim

To get this information into @code{chordNameExceptions} takes a little
manoeuvring. The following code transforms @code{chExceptionMusic}
(which is a sequential music) into a list of exceptions.
@example
        (sequential-music-to-chord-exceptions chExceptionMusic #t)
@end example
Then,
@example
(append
 (sequential-music-to-chord-exceptions chExceptionMusic #t)
 ignatzekExceptions)
@end example
adds the new exceptions to the default ones, which are defined in
@file{ly/@/chord@/-modifier@/-init@/.ly}.

For an example of tuning this property, see also
@inputfileref{input/@/regression,chord@/-name@/-exceptions@/.ly}.
@cindex exceptions, chord names.


@cindex @code{majorSevenSymbol}
@item majorSevenSymbol
This property contains the markup object used for the 7th step, when
it is major.  Predefined options are @code{whiteTriangleMarkup} and
@code{blackTriangleMarkup}.  See
@inputfileref{input/@/regression,chord@/-name@/-major7@/.ly} for an example.

@cindex @code{chordNameSeparator}
@item chordNameSeparator
Different parts of a chord name are normally separated by a
slash.  By setting @code{chordNameSeparator}, you can specify other
separators, e.g.
@lilypond[quote,raggedright,fragment,verbatim]
\context ChordNames \chordmode {
  c:7sus4
  \set chordNameSeparator
    = \markup { \typewriter "|" }
  c:7sus4
}
@end lilypond

@cindex @code{chordRootNamer}
@item chordRootNamer
The root of a chord is usually printed as a letter with an optional
alteration.  The transformation from pitch to letter is done by this
function.  Special note names (for example, the German ``H'' for a
B-chord) can be produced by storing a new function in this property.

@cindex @code{chordNoteNamer}
@item chordNoteNamer
The default is to print single pitch, e.g. the bass note, using the
@code{chordRootNamer}.  The @code{chordNoteNamer} property can be set
to a specialized function to change this behavior.  For example, the
base can be printed in lower case.

@end table

The predefined variables @code{\germanChords},
@code{\semiGermanChords} set these variables.  The effect is
demonstrated here,

@lilypondfile[raggedright]{chord-names-german.ly}

There are also two other chord name schemes implemented: an alternate
Jazz chord notation, and a systematic scheme called Banter chords.  The
alternate jazz notation is also shown on the chart in @ref{Chord name
chart}.  Turning on these styles is described in the input file
@inputfileref{input/@/test,chord@/-names@/-jazz@/.ly}.

@cindex Banter
@cindex jazz chords
@cindex chords, jazz  


@refcommands

@cindex @code{\germanChords}
@code{\germanChords}, 
@cindex @code{\semiGermanChords}
@code{\semiGermanChords}.




@seealso

Examples: @inputfileref{input/@/regression,chord@/-name@/-major7@/.ly},
@inputfileref{input/@/regression,chord@/-name@/-exceptions@/.ly},
@inputfileref{input/@/test,chord@/-names@/-jazz@/.ly},
@inputfileref{input/@/test,chords@/-without@/-melody@/.ly}.


Init files: @file{scm/@/chords@/-ignatzek@/.scm}, and
@file{scm/@/chord@/-entry@/.scm}.


@refbugs

Chord names are determined solely from the list of pitches.  Chord
inversions are not identified, and neither are added bass notes.  This
may result in strange chord names when chords are entered with the
@code{< .. >} syntax.


@node Fret diagrams
@subsection Fret diagrams
@cindex fret diagrams
@cindex chord diagrams

Fret diagrams can be added to music as a markup to the desired note. The
markup contains information about the desired fret diagram, as shown in the
following example

@lilypond[verbatim, raggedright, quote]
\context Voice {
  d' ^\markup \fret-diagram #"6-x;5-x;4-o;3-2;2-3;1-2;"
  d' d' d'
  fis' ^\markup \override #'(size . 0.75) {
    \override #'(finger-code . below-string) {
      \fret-diagram-verbose #'((place-fret 6 2 1) (barre 6 1 2)
                               (place-fret 5 4 3) (place-fret 4 4 4)
                               (place-fret 3 3 2) (place-fret 2 2 1)
                               (place-fret 1 2 1))
    }
  }
  fis' fis' fis'
  c' ^\markup  \override #'(dot-radius . 0.35) {
    \override #'(finger-code . in-dot) {
      \override #'(dot-color . white) {
        \fret-diagram-terse #"x;3-1-(;5-2;5-3;5-4;3-1-);"
      }
    }
  }
  c' c' c'
}
@end lilypond


There are three different fret-diagram markup interfaces: standard, terse,
and verbose.  The three interfaces produce equivalent markups, but have
varying amounts of information in the markup string.  Details about the
markup interfaces are found at @ref{Overview of text markup commands}. 

You can set a number of graphical properties according to your preference.
Details about the property interface to fret diagrams are found at 
@internalsref{fret-diagram-interface}.


@seealso

Examples: @inputfileref{input/@/test,fret@/-diagram@/.ly}


@node Improvisation
@subsection Improvisation

Improvisation is sometimes denoted with slashed note heads.  Such note
heads can be created by adding a @internalsref{Pitch_squash_engraver}
to the @internalsref{Staff} or @internalsref{Voice} context.  Then, the
following command

@example
    \set squashedPosition = #0
    \override NoteHead  #'style = #'slash
@end example

@noindent
switches on the slashes.

There are shortcuts @code{\improvisationOn} (and an accompanying
@code{\improvisationOff}) for this command sequence.  They are used in
the following example

@lilypond[verbatim,raggedright,quote]
\new Staff \with {
  \consists Pitch_squash_engraver
} \transpose c c' {
  e8 e g a a16(bes)(a8) g \improvisationOn
  e8
  ~e2~e8 f4 fis8
  ~fis2 \improvisationOff a16(bes) a8 g e
}
@end lilypond



@node Orchestral music
@section Orchestral music

@cindex  Writing parts

Orchestral music involves some special notation, both in the full
score and the individual parts.  This section explains how to tackle
some common problems in orchestral music.



@menu
* System start delimiters::     
* Aligning to cadenzas::        
* Rehearsal marks::             
* Bar numbers::                 
* Instrument names::            
* Transpose::                   
* Instrument transpositions::   
* Multi measure rests::         
* Automatic part combining::    
* Hiding staves::               
* Different editions from one source::  
* Quoting other voices::        
* Formatting cue notes::        
@end menu

@node System start delimiters
@subsection  System start delimiters

Polyphonic scores consist of many staves.  These staves can be
constructed in three different ways
@itemize @bullet
@item The group is started with a brace at the left, and bar lines are
connected.  This is done with the @internalsref{GrandStaff} context.

@lilypond[verbatim,raggedright,quote]
\new GrandStaff
\relative <<
  \new Staff { c1 c }
  \new Staff { c c }
>>
@end lilypond 


@item The group is started with a bracket, and bar lines are connected.  This is done with the
@internalsref{StaffGroup} context

@lilypond[verbatim,raggedright,quote]
\new StaffGroup
\relative <<
  \new Staff { c1 c }
  \new Staff { c c }
>>
@end lilypond 


@item The group is started with a vertical line.  Bar lines are not
connected.  This is the default for the score.

@lilypond[verbatim,raggedright,quote]
\relative <<
  \new Staff { c1 c }
  \new Staff { c c }
>>
@end lilypond 

@end itemize

@cindex Staff, multiple
@cindex bracket, vertical
@cindex brace, vertical
@cindex grand staff
@cindex staff group


@seealso

The bar lines at the start of each system are
@internalsref{SystemStartBar}, @internalsref{SystemStartBrace}, and
@internalsref{SystemStartBracket}.  Only one of these types is created
in every context, and that type is determined by the property
@code{systemStartDelimiter}.

@node Aligning to cadenzas
@subsection Aligning to cadenzas


In an orchestral context, cadenzas present a special problem:
when constructing a score that includes a cadenza, all other
instruments should skip just as many notes as the length of the
cadenza, otherwise they will start too soon or too late. 

A solution to this problem are the functions @code{mmrest-of-length}
and @code{skip-of-length}.  These Scheme functions take a piece music
as argument, and generate a @code{\skip} or multi rest, exactly as
long as the piece.  The use of @code{mmrest-of-length} is demonstrated
in the following example. 

@lilypond[verbatim,raggedright,quote]
cadenza =  \relative c' {
  c4 d8 << { e f g } \\ { d4. } >>
  g4 f2 g4 g
}
    
\new GrandStaff <<
  \new Staff { \cadenza c'4 } 
  \new Staff {
    #(ly:export (mmrest-of-length cadenza))
    c'4
  }
>>
@end lilypond





@node Rehearsal marks
@subsection Rehearsal marks
@cindex Rehearsal marks
@cindex mark
@cindex @code{\mark}

To print a rehearsal mark, use the @code{\mark} command

@lilypond[quote,raggedright,fragment,verbatim,relative=1]
  c1 \mark \default
  c1 \mark \default
  c1 \mark #8 
  c1 \mark \default
  c1 \mark \default
@end lilypond

@noindent
(The letter I is skipped in accordance with engraving traditions.)
@c  umm, is the manual the right place for feature requests?  :)  -gp
@c FIXME - should make that tunable.

The mark is incremented automatically if you use @code{\mark
\default}, but you can also use an integer argument to set the mark
manually.  The value to use is stored in the property
@code{rehearsalMark}.

The style is defined by the property @code{markFormatter}.  It is a
function taking the current mark (an integer) and the current context
as argument.  It should return a markup object.  In the following
example, @code{markFormatter} is set to a canned procedure.  After a
few measures, it is set to function that produces a boxed number. 

@c  fragproblem? -gp
@lilypond[quote,raggedright,verbatim,relative=2]
{
  \set Score.markFormatter = #format-mark-numbers 
  c1 \mark \default
  c1 \mark \default
  \set Score.markFormatter
     = #(lambda (mark context)
         (make-bold-markup
          (make-box-markup (number->string mark))))
  c1 \mark \default
  c1 \mark \default
}
@end lilypond

The file @file{scm/@/translation@/-functions@/.scm} contains the definitions
of @code{format-mark-numbers} (the default format) and
@code{format-mark-letters}.  These can be used as inspiration for other
formatting functions.


@cindex coda on bar line
@cindex segno on bar line
@cindex fermata on bar line
@cindex bar lines, symbols on

The @code{\mark} command can also be used to put signs like coda,
segno and fermatas on a bar line.  Use @code{\markup} to
to access the appropriate symbol

@c fragproblem? -gp
@lilypond[quote,raggedright,verbatim,relative=2]
{
  c1 \mark \markup { \musicglyph #"scripts-ufermata" }
  c1
}
@end lilypond

In the case of a line break, marks must also be printed at the end of
the line, and not at the beginning.  Use the following to force that
behavior
@example
  \override Score.RehearsalMark  
    #'break-visibility = #begin-of-line-invisible
@end example

@cindex fermatas
@cindex coda
@cindex segno
@cindex bar lines, putting symbols on 

@seealso

Program reference: @internalsref{MarkEvent}, @internalsref{RehearsalMark}.

Init files: @file{scm/@/translation@/-functions@/.scm} contains the
definition of @code{format-mark-numbers} and
@code{format-mark-letters}.  They can be used as inspiration for other
formatting functions.

Examples: @inputfileref{input/@/regression,rehearsal@/-mark@/-letter@/.ly},

@inputfileref{input/@/regression,rehearsal@/-mark@/-number@/.ly}.


@node Bar numbers
@subsection Bar numbers


@cindex bar numbers
@cindex measure numbers
@cindex @code{currentBarNumber}

Bar numbers are printed by default at the start of the line.  The
number itself is stored in the @code{currentBarNumber} property, which
is normally updated automatically for every measure.

Bar numbers can be typeset at regular intervals instead of at the
beginning of each line.  This is illustrated in the following example,
whose source is available as
@inputfileref{input/@/test,bar@/-number@/-regular@/-interval@/.ly}

@lilypondfile[raggedright,quote]{bar-number-regular-interval.ly}

Bar numbers can be manually changed by setting the
@code{Staff.currentBarNumber} property

@c fragproblem?  -gp
@lilypond[raggedright,quote]
\relative c' {
  \repeat unfold 4 {c4 c c c} \break
  \set Score.currentBarNumber = #50
  \repeat unfold 4 {c4 c c c}
}
@end lilypond

@seealso

Program reference: @internalsref{BarNumber}.

Examples:
@inputfileref{input/@/test,bar@/-number@/-every@/-five@/-reset@/.ly},
and @inputfileref{input/@/test,bar@/-number@/-regular@/-interval@/.ly}.

@refbugs

Bar numbers can collide with the @internalsref{StaffGroup} bracket, if
there is one at the top.  To solve this, the
@code{padding} property of @internalsref{BarNumber} can be
used to position the number correctly.

@node Instrument names
@subsection Instrument names

In an orchestral score, instrument names are printed left side of the
staves.

This can be achieved by setting @internalsref{Staff}.@code{instrument}
and @internalsref{Staff}.@code{instr}.  This will print a string before
the start of the staff.  For the first start, @code{instrument} is
used, for the next ones @code{instr} is used.

@lilypond[quote,verbatim,raggedright,relative=1,fragment]
  \set Staff.instrument = "Ploink "
  \set Staff.instr = "Plk "
  c1
  \break
  c''
@end lilypond

You can also use markup texts to construct more complicated instrument
names, for example

@lilypond[quote,fragment,verbatim,raggedright]
  \set Staff.instrument = \markup {
    \column < "Clarinetti" { "in B"
      \smaller \flat } > }
{ c''1 }
@end lilypond

For longer instrument names, it may be useful to increase the
@code{indent} setting in the @code{\layout} block.

@seealso

Program reference: @internalsref{InstrumentName}.

@refbugs

When you put a name on a grand staff or piano staff the width of the
brace is not taken into account.  You must add extra spaces to the end of
the name to avoid a collision.

@node Transpose
@subsection Transpose
@cindex Transpose
@cindex transposition of pitches
@cindex @code{\transpose}

A music expression can be transposed with @code{\transpose}.  The
syntax is
@example
  \transpose @var{from} @var{to} @var{musicexpr}
@end example

This means that @var{musicexpr} is transposed by the interval between
the pitches @var{from} and @var{to}: any note with pitch @code{from}
is changed to @code{to}.


For example, consider a piece written in the key of  D major.  If
this piece is a little too low for its performer, it can be
transposed up to E major with
@example
  \transpose d e @dots{}
@end example

Consider a part written for violin (a C instrument).  If
this part is to be played on the A clarinet, the following
transposition will produce the appropriate part

@example
  \transpose a c @dots{}
@end example   

@code{\transpose} distinguishes between enharmonic pitches: both
@code{\transpose c cis} or @code{\transpose c des} will transpose up
half a tone.  The first version will print sharps and the second
version will print flats

@lilypond[quote,raggedright,verbatim]
mus = { \key d \major cis d fis g }
\context Staff {
  \clef "F" \mus
  \clef "G"
  \transpose c g' \mus
  \transpose c f' \mus
}
@end lilypond


@seealso

Program reference: @internalsref{TransposedMusic}, and
@internalsref{UntransposableMusic}.

@refbugs

If you want to use both @code{\transpose} and @code{\relative},
you must put @code{\transpose} outside of @code{\relative}, since
@code{\relative} will have no effect music that appears inside a
@code{\transpose}.

@node Instrument transpositions
@subsection Instrument transpositions

The key of a transposing instrument can also be specified.  This
applies to many wind instruments, for example, clarinets (B-flat, A and
E-flat), horn (F) and trumpet (B-flat, C, D and E-flat).

The transposition is entered after the keyword @code{\transposition}

@example
  \transposition bes   %%  B-flat clarinet
@end example

@noindent
This command sets the property @code{instrumentTransposition}.  The value of
this property is used for MIDI output and quotations.  It does not
affect how notes are printed in the current staff.

The pitch to use for @code{\transposition} should correspond to the
transposition of the notes. For example, when entering a score in
concert pitch, typically all voices are entered in C, so 
they should be entered as

@example
  clarinet = @{
    \transposition c'
    ...
  @}
  saxophone  = @{
    \transposition c'
    ..
  @}
@end example

The command @code{\transposition} should be used when the music is
entered from a (transposed) orchestral part.  For example, in
classical horn parts, the tuning of the instrument is often changed
during a piece. When copying the notes from the part, use
@code{\transposition}, e.g.

@example
  \transposition d'
  c'4^"in D"
  ...
  \transposition g'
  c'4^"in G"
  ...
@end example
 


@cindex transposition, MIDI
@cindex transposition, instrument


@node Multi measure rests
@subsection Multi measure rests
@cindex multi measure rests
@cindex Rests, multi measure

@cindex @code{R}

Multi measure rests are entered using `@code{R}'.  It is specifically
meant for full bar rests and for entering parts: the rest can expand
to fill a score with rests, or it can be printed as a single
multimeasure rest.  This expansion is controlled by the property
@code{Score.skipBars}.  If this is set to true, empty measures will not
be expanded, and the appropriate number is added automatically

@lilypond[quote,raggedright,fragment,verbatim]
  \time 4/4 r1 | R1 | R1*2
  \set Score.skipBars = ##t R1*17  R1*4
@end lilypond

The @code{1} in @code{R1} is similar to the duration notation used for
notes.  Hence, for time signatures other than 4/4, you must enter other
durations.  This can be done with augmentation dots or fractions

@lilypond[quote,raggedright,fragment,verbatim]
  \set Score.skipBars = ##t
  \time 3/4
  R2. | R2.*2
  \time 13/8
  R1*13/8
  R1*13/8*12 |
  \time 10/8 R4*5*4 |
@end lilypond

An @code{R} spanning a single measure is printed as either a whole rest
or a breve, centered in the measure regardless of the time signature.

If there are only a few measures of rest, LilyPond prints ``church rests''
(a series of rectangles) in the staff.  To replace that with a simple
rest, use @code{MultiMeasureRest.expand-limit}.

@lilypond[quote,raggedright,fragment,verbatim]
  \set Score.skipBars = ##t
  R1*2 | R1*5 | R1*9
  \override MultiMeasureRest #'expand-limit = 1
  R1*2 | R1*5 | R1*9
@end lilypond


@cindex text on multi-measure rest
@cindex script on multi-measure rest
@cindex fermata on multi-measure rest

Texts can be added to multi-measure rests by using the
@var{note}-@code{markup} syntax (see @ref{Text markup}).  
A variable (@code{\fermataMarkup}) is provided for
adding fermatas


@lilypond[quote,raggedright,verbatim,fragment]
  \set Score.skipBars = ##t
  \time 3/4
  R2.*10^\markup { "Ad lib" }
  R2.^\fermataMarkup
@end lilypond

If you want to have a text on the left end of a multi-measure rest,
attach the text to a zero-length skip note, i.e.

@example
  s1*0^"Allegro"
  R1*4 
@end example


@cindex whole rests for a full measure 

@seealso

Program reference: @internalsref{MultiMeasureRestEvent},
@internalsref{MultiMeasureTextEvent},
@internalsref{MultiMeasureRestMusicGroup}, and
@internalsref{MultiMeasureRest}.

The layout object @internalsref{MultiMeasureRestNumber} is for the
default number, and @internalsref{MultiMeasureRestText} for user
specified texts.

@refbugs

It is not possible to use fingerings (e.g. @code{R1-4}) to put numbers
over multi-measure rests.

@cindex condensing rests

There is no way to automatically condense multiple rests into a single
multimeasure rest.  Multi measure rests do not take part in rest
collisions.

Be careful when entering multimeasure rests followed by whole
notes.  The following will enter two notes lasting four measures each
@example
  R1*4 cis cis 
@end example
When @code{skipBars} is set, the result will look OK, but the bar
numbering will be off.

@node Automatic part combining
@subsection Automatic part combining
@cindex automatic part combining
@cindex part combiner


Automatic part combining is used to merge two parts of music onto a
staff.  It is aimed at typesetting orchestral scores.  When the two
parts are identical for a period of time, only one is shown.  In
places where the two parts differ, they are typeset as separate
voices, and stem directions are set automatically.  Also, solo and
@emph{a due} parts are identified and can be marked.

The syntax for part combining is

@example
  \partcombine @var{musicexpr1} @var{musicexpr2}
@end example



The following example demonstrates the basic functionality of the part
combiner: putting parts on one staff, and setting stem directions and
polyphony

@lilypond[quote,verbatim,raggedright,fragment]
\new Staff \partcombine
  \relative g' { g g a( b) c c r r }
  \relative g' { g g r4 r e e g g }
@end lilypond

The first @code{g} appears only once, although it was
specified twice (once in each part).  Stem, slur and tie directions are
set automatically, depending whether there is a solo or unisono.  The
first part (with context called @code{one}) always gets up stems, and
`solo', while the second (called @code{two}) always gets down stems and
`Solo II'.

If you just want the merging parts, and not the textual markings, you
may set the property @code{printPartCombineTexts} to false

@lilypond[quote,verbatim,raggedright,fragment,relative=2]
\new Staff <<
  \set Staff.printPartCombineTexts = ##f
  \partcombine
    \relative g' { g a( b) r }
    \relative g' { g r4 r f }
>>
@end lilypond


Both arguments to @code{\partcombine} will be interpreted as
@internalsref{Voice} contexts.  If using relative octaves,
@code{\relative} should be specified for both music expressions, i.e.

@example
\partcombine
  \relative @dots{} @var{musicexpr1}
  \relative @dots{} @var{musicexpr2}
@end example

@noindent
A @code{\relative} section that is outside of @code{\partcombine} has
no effect on the pitches of @var{musicexpr1} and @var{musicexpr2}.

@seealso

Program reference: @internalsref{PartCombineMusic},
@internalsref{SoloOneEvent}, and
@internalsref{SoloTwoEvent}, and
@internalsref{UnisonoEvent}.

@refbugs

When @code{printPartCombineTexts} is set, when the two voices play the
same notes on and off, the part combiner may typeset @code{a2} more
than once in a measure.

@code{\partcombine} cannot be inside @code{\times}. 

@code{\partcombine} cannot be inside @code{\relative}. 

Internally, the @code{\partcombine} interprets both arguments as
@code{Voice}s named @code{one} and @code{two}, and then decides when
the parts can be combined.  Consequently, if the arguments switch to
differently named @internalsref{Voice} contexts, the events in those
will be ignored.

@node Hiding staves
@subsection Hiding staves

@cindex Frenched scores
@cindex Hiding staves

In orchestral scores, staff lines that only have rests are usually
removed.  This saves some space.  This style is called `French Score'.
For @internalsref{Lyrics}, 
@internalsref{ChordNames} and @internalsref{FiguredBass}, this is
switched on by default.  When these line of these contexts turn out
empty after the line-breaking process, they are removed.

For normal staves, a specialized @internalsref{Staff} context is
available, which does the same: staves containing nothing (or only
multi measure rests) are removed.  The context definition is stored in
@code{\RemoveEmptyStaffContext} variable.  Observe how the second staff
in this example disappears in the second line


@lilypond[quote,raggedright,verbatim]
\layout {
  \context { \RemoveEmptyStaffContext }
}

{
  \relative c' <<
    \new Staff { e4 f g a \break c1 }
    \new Staff { c4 d e f \break R1 }
  >>
}
@end lilypond

The first system shows all staves in full.  If empty staves should be
removed from the first system too, set @code{remove-first} to false in
@internalsref{RemoveEmptyVerticalGroup}.

Another application is making ossia sections, i.e. alternative
melodies on a separate piece of staff, with help of a Frenched
staff.  See @inputfileref{input/@/test,ossia@/.ly} for an example.


@node Different editions from one source
@subsection Different editions from one source

The @code{\tag} command marks music expressions with a name.  These
tagged expressions can be filtered out later.  With this mechanism it
is possible to make different versions of the same music source.

In the following example, we see two versions of a piece of music, one
for the full score, and one with cue notes for the instrumental part

@example
  c1
  <<
    \tag #'part <<
      R1 \\
      @{
        \set fontSize = #-1
        c4_"cue" f2 g4 @} 
    >>
    \tag #'score R1
  >>
  c1
@end example

The same can be applied to articulations, texts, etc.: they are
made by prepending
@example
  -\tag #@var{your-tag} 
@end example
to an articulation, for example, 
@example
  c1-\tag #'part ^4
@end example

This defines a note with a conditional fingering indication.

By applying the @code{\keepWithTag} and @code{\removeWithTag}
commands, tagged expressions can be filtered.  For example,
@example
<<
  @var{the music}
  \keepWithTag #'score @var{the music}
  \keepWithTag #'part @var{the music}
>>
@end example
would yield

@lilypondfile[raggedright,quote]{tag-filter.ly}


The argument of the @code{\tag} command should be a symbol, or a list
of symbols, for example,
@example
  \tag #'(original-part transposed-part) @dots{}
@end example



@seealso

Examples: @inputfileref{input/@/regression,tag@/-filter@/.ly}.

@refbugs

Multiple rests are not merged if you create the score with both tagged
sections.

@node Quoting other voices
@subsection Quoting other voices

With quotations, fragments of other parts can be inserted into a part
directly.  Before a part can be quoted, it must be marked especially as
quotable.  This is done with code @code{\addquote} command.

@example
  \addquote @var{name} @var{music}
@end example


@noindent
Here, @var{name} is an identifying string.  The @var{music} is any kind
of music.  This is an example of @code{\addquote}

@verbatim
\addquote clarinet \relative c' {
  f4 fis g gis
}
@end verbatim

This command must be entered at toplevel, i.e.  outside any music
blocks.

After calling @code{\addquote}, the quotation may then be done with
@code{\quote},

@example
  \quote @var{name} @var{duration}  
@end example

During a part, a piece of music can be quoted with the @code{\quote}
command. 
  
@example
\quote clarinet 2.
@end example

This would cite three quarter notes (@code{2.} is a dotted half note)
of the previously added @code{clarinet} voice.

More precisely, it takes the current time-step of the part being
printed, and extracts the notes at the corresponding point of the
@code{\addquote}d voice.  Therefore, the argument to @code{\addquote}
should be the entire part of the voice to be quoted, including any
rests at the beginning. 

Quotations take into account the transposition of both source and target
instruments, if they are specified using the @code{\transposition} command.

@lilypond[quote,raggedright,verbatim]
\addquote clarinet \relative c' {
  \transposition bes
  f4 fis g gis
}

{
  e'8 f'8 \quote clarinet 2
}
@end lilypond

The type of events that are present in cue notes can be trimmed with
the @code{quotedEventTypes} property. The default value is
@code{(note-event rest-event)}, which means that only notes of and
rests of the cued voice end up in the @code{\quote}.
Setting

@example
\set Staff.quotedEventTypes =
       #'(note-event articulation-event dynamic-event)  
@end example

@noindent
will quote notes (but no rests), together with scripts and dynamics.
 
@refbugs

Only the contents of the first @internalsref{Voice} occurring in an
@code{\addquote} command will be considered for quotation, so
@var{music} can not contain @code{\new} and @code{\context Voice}
statements that would switch to a different Voice.

Quoting grace notes is broken and can even cause LilyPond to crash.

@seealso

In this manual: @ref{Instrument transpositions}.

Examples: @inputfileref{input/@/regression,quote@/.ly}
@inputfileref{input/@/regression,quote@/-transposition@/.ly}

Program reference: @internalsref{QuoteMusic}.

@node Formatting cue notes
@subsection Formatting cue notes


The previous section deals with inserting notes from another
voice.  When making a part, these notes need to be specially formatted.
Here is an example of formatted cue notes

@c TODO: This should be done with \quote stuff, not manually.

@lilypond[raggedright,verbatim]
smaller = {
  \set fontSize = #-1
  \override Stem  #'length = #5.5
  \override Beam  #'thickness = #0.384
  \override Beam  #'space-function =
    #(lambda (beam mult) (* 0.8 (Beam::space_function beam mult)))
}

{
  \set Staff.instrument = #"Horn in F"
  \set Score.skipBars = ##t
  R1*21
  << {
    \once \override Staff.MultiMeasureRest  #'staff-position = #-6
    R1
  }
  \new Voice {
    s2
    \clef tenor
    \smaller
    r8^"Bsn." c'8  f'8[ f'8]
    \clef treble
  }
  >>
  c'8^"Horn" cis'
  eis'4 fis'4
}
@end lilypond


There are a couple of points to take care of:

@itemize @bullet
@item
The multi rest of the original part should be moved up or down during
the cue.
@item
Cue notes have smaller font sizes.
@item
When cued notes have a clef change relative to the original part, the
clef should be restored after the cue section.  This minimizes
confusion for the reader,
@item
When the original part starts, this should be marked with the name of
the instrument, in this case ``Horn.''   Of course, the cue part is
marked with the instrument playing the cue.
@end itemize

@c  really?  Are you sure about that last point?  I'll check after 3.0 -gp 


@node Ancient notation
@section Ancient notation

@cindex Vaticana, Editio
@cindex Medicaea, Editio
@cindex hufnagel
@cindex Petrucci
@cindex mensural

Support for ancient notation includes features for mensural notation
and Gregorian Chant notation.  There is also limited support for
figured bass notation.

Many graphical objects provide a @code{style} property, see
@itemize @bullet
@item
@ref{Ancient note heads},
@item
@ref{Ancient accidentals},
@item
@ref{Ancient rests},
@item
@ref{Ancient clefs},
@item
@ref{Ancient flags},
@item
@ref{Ancient time signatures}.
@end itemize

By manipulating such a grob property, the typographical appearance of
the affected graphical objects can be accommodated for a specific
notation flavor without need for introducing any new notational
concept.

In addition to the standard articulation signs described in section
@ref{Articulations}, specific articulation signs for ancient notation
are provided.

@itemize @bullet
@item
@ref{Ancient articulations}
@end itemize

Other aspects of ancient notation can not that easily be expressed as
in terms of just changing a style property of a graphical object or
adding articulation signs.  Some notational concepts are introduced
specifically for ancient notation,

@itemize @bullet
@item
@ref{Custodes},
@item
@ref{Divisiones},
@item
@ref{Ligatures}.
@end itemize

If this all is too much of documentation for you, and you just want to
dive into typesetting without worrying too much about the details on
how to customize a context, you may have a look at the predefined
contexts.  Use them to set up predefined style-specific voice and
staff contexts, and directly go ahead with the note entry,

@itemize @bullet
@item
@ref{Gregorian Chant contexts},
@item
@ref{Mensural contexts}.
@end itemize

There is limited support for figured bass notation which came
up during the baroque period.

@itemize @bullet
@item
@ref{Figured bass}
@end itemize

Here are all suptopics at a glance:

@menu
* Ancient note heads::          
* Ancient accidentals::         
* Ancient rests::               
* Ancient clefs::               
* Ancient flags::               
* Ancient time signatures::     
* Ancient articulations::       
* Custodes::                    
* Divisiones::                  
* Ligatures::                   
* Gregorian Chant contexts::    
* Mensural contexts::           
* Figured bass::                
@end menu


@node Ancient note heads
@subsection Ancient note heads

@cindex note heads


For ancient notation, a note head style other than the @code{default}
style may be chosen.  This is accomplished by setting the @code{style}
property of the NoteHead object to @code{baroque}, @code{neomensural}
or @code{mensural}.  The @code{baroque} style differs from the
@code{default} style only in using a square shape for @code{\breve}
note heads.  The @code{neomensural} style differs from the
@code{baroque} style in that it uses rhomboidal heads for whole notes
and all smaller durations.  Stems are centered on the note heads.
This style is in particular useful when transcribing mensural music,
e.g. for the incipit.  The @code{mensural} style finally produces note
heads that mimic the look of note heads in historic printings of the
16th century.

The following example demonstrates the @code{neomensural} style

@lilypond[quote,fragment,raggedright,verbatim]
  \set Score.skipBars = ##t
  \override NoteHead #'style = #'neomensural
  a'\longa a'\breve a'1 a'2 a'4 a'8 a'16
@end lilypond

When typesetting a piece in Gregorian Chant notation, the
@internalsref{Gregorian_ligature_engraver} will automatically select
the proper note heads, such there is no need to explicitly set the
note head style.  Still, the note head style can be set e.g.@: to
@code{vaticana_punctum} to produce punctum neumes.  Similarly, a
@internalsref{Mensural_ligature_engraver} is used to automatically
assemble mensural ligatures.  See @ref{Ligatures} for how ligature
engravers work.

@seealso

Examples: @inputfileref{input/@/regression,note@/-head@/-style@/.ly} gives an
overview over all available note head styles.


@node Ancient accidentals
@subsection Ancient accidentals

@cindex accidentals


Use the @code{style} property of grob @internalsref{Accidental} to
select ancient accidentals.   Supported styles are
@code{mensural}, @code{vaticana}, @code{hufnagel} and @code{medicaea}.

@lilypond[quote,raggedright,staffsize=26]
\score {
{
  \fatText
  s^\markup {
    \column <
      "vaticana" 
      { " " \musicglyph #"accidentals-vaticana-1"
      " " \musicglyph #"accidentals-vaticana0" }
    >
    \column <
      "medicaea"
      { " " \musicglyph #"accidentals-medicaea-1" }
    >
    \column <
      "hufnagel"
      { " " \musicglyph #"accidentals-hufnagel-1" }
    >
    \column <
      "mensural"
      { " " \musicglyph #"accidentals-mensural-1"
      " " \musicglyph #"accidentals-mensural1" }
    >
  }
}
\layout {
  interscoreline = 1
  \context { \Score \remove "Bar_number_engraver" }
  \context { \Staff
      \remove "Clef_engraver"
      \remove "Key_engraver"
      \remove "Time_signature_engraver"
      \remove "Staff_symbol_engraver"
      minimumVerticalExtent = ##f
    }
  }
}
@end lilypond

As shown, not all accidentals are supported by each style.  When
trying to access an unsupported accidental, LilyPond will switch to a
different style, as demonstrated in
@inputfileref{input/@/test,ancient@/-accidentals@/.ly}.

Similarly to local accidentals, the style of the key signature can be
controlled by the @code{style} property of the
@internalsref{KeySignature} grob.

@seealso

In this manual: @ref{Pitches}, @ref{Chromatic alterations} and
@ref{Accidentals} give a general introduction into the use of
accidentals.  @ref{Key signature} gives a general introduction into
the use of key signatures.

Program reference: @internalsref{KeySignature}.

Examples: @inputfileref{input/@/test,ancient@/-accidentals@/.ly}.

@node Ancient rests
@subsection Ancient rests

@cindex rests


Use the @code{style} property of grob @internalsref{Rest} to select
ancient accidentals.   Supported styles are @code{classical},
@code{neomensural} and @code{mensural}.  @code{classical} differs
from the @code{default} style only in that the quarter rest looks like
a horizontally mirrored 8th rest.  The @code{neomensural} style suits
well for e.g. the incipit of a transcribed mensural piece of music.
The @code{mensural} style finally mimics the appearance of rests as
in historic prints of the 16th century.

The following example demonstrates the @code{neomensural} style

@lilypond[quote,fragment,raggedright,verbatim]
  \set Score.skipBars = ##t 
  \override Rest #'style = #'neomensural
  r\longa r\breve r1 r2 r4 r8 r16
@end lilypond

There are no 32th and 64th rests specifically for the mensural or
neo-mensural style.  Instead, the rests from the default style will be
taken.  See @inputfileref{input/@/test,rests@/.ly} for a chart of all
rests.

There are no rests in Gregorian Chant notation; instead, it uses
@ref{Divisiones}.

@seealso

In this manual: @ref{Rests} gives a general introduction into the use of rests.


@node Ancient clefs
@subsection Ancient clefs

@cindex clefs


LilyPond supports a variety of clefs, many of them ancient.

The following table shows all ancient clefs that are supported via the
@code{\clef} command.  Some of the clefs use the same glyph, but
differ only with respect to the line they are printed on.  In such
cases, a trailing number in the name is used to enumerate these clefs.
Still, you can manually force a clef glyph to be typeset on an
arbitrary line, as described in @ref{Clef}.  The note printed to the
right side of each clef in the example column denotes the @code{c'}
with respect to that clef.

@multitable @columnfractions .4 .4 .2
@item
@b{Description}
@tab
@b{Supported Clefs}
@tab
@b{Example}

@item
modern style mensural C clef
@tab
@code{neomensural-c1}, @code{neomensural-c2},@*
@code{neomensural-c3}, @code{neomensural-c4}
@tab
@lilypond[fragment,relative=1,notime]
  \clef "neomensural-c2" c
@end lilypond

@item
petrucci style mensural C clefs, for use on different staff lines
(the examples shows the 2nd staff line C clef)
@tab
@code{petrucci-c1}, @code{petrucci-c2},@*
@code{petrucci-c3}, @code{petrucci-c4},@*
@code{petrucci-c5}
@tab
@lilypond[fragment,relative=1,notime]
  \clef "petrucci-c2" c
@end lilypond

@item
petrucci style mensural F clef
@tab
@code{petrucci-f}
@tab
@lilypond[fragment,relative=1,notime]
  \clef "petrucci-f" c
@end lilypond

@item
petrucci style mensural G clef
@tab
@code{petrucci-g}
@tab
@lilypond[fragment,relative=1,notime]
  \clef "petrucci-g" c
@end lilypond

@item
historic style mensural C clef
@tab
@code{mensural-c1}, @code{mensural-c2},@*
@code{mensural-c3}, @code{mensural-c4}
@tab
@lilypond[fragment,relative=1,notime]
  \clef "mensural-c2" c
@end lilypond

@item
historic style mensural F clef
@tab
@code{mensural-f}
@tab
@lilypond[fragment,relative=1,notime]
  \clef "mensural-f" c
@end lilypond

@item
historic style mensural G clef
@tab
@code{mensural-g}
@tab
@lilypond[fragment,relative=1,notime]
  \clef "mensural-g" c
@end lilypond

@item
Editio Vaticana style do clef
@tab
@code{vaticana-do1}, @code{vaticana-do2},@*
@code{vaticana-do3}
@tab
@lilypond[fragment,relative=1,notime]
  \override Staff.StaffSymbol   #'line-count = #4
  \clef "vaticana-do2" c
@end lilypond

@item
Editio Vaticana style fa clef
@tab
@code{vaticana-fa1}, @code{vaticana-fa2}
@tab
@lilypond[fragment,relative=1,notime]
  \override Staff.StaffSymbol   #'line-count = #4
  \clef "vaticana-fa2" c
@end lilypond

@item
Editio Medicaea style do clef
@tab
@code{medicaea-do1}, @code{medicaea-do2},@*
@code{medicaea-do3}
@tab
@lilypond[fragment,relative=1,notime]
  \override Staff.StaffSymbol   #'line-count = #4
  \clef "medicaea-do2" c
@end lilypond

@item
Editio Medicaea style fa clef
@tab
@code{medicaea-fa1}, @code{medicaea-fa2}
@tab
@lilypond[fragment,relative=1,notime]
  \override Staff.StaffSymbol   #'line-count = #4
  \clef "medicaea-fa2" c
@end lilypond

@item
historic style hufnagel do clef
@tab
@code{hufnagel-do1}, @code{hufnagel-do2},@*
@code{hufnagel-do3}
@tab
@lilypond[fragment,relative=1,notime]
  \override Staff.StaffSymbol   #'line-count = #4
  \clef "hufnagel-do2" c
@end lilypond

@item
historic style hufnagel fa clef
@tab
@code{hufnagel-fa1}, @code{hufnagel-fa2}
@tab
@lilypond[fragment,relative=1,notime]
  \override Staff.StaffSymbol   #'line-count = #4
  \clef "hufnagel-fa2" c
@end lilypond

@item
historic style hufnagel combined do/fa clef
@tab
@code{hufnagel-do-fa}
@tab
@lilypond[fragment,relative=1,notime]
  \clef "hufnagel-do-fa" c
@end lilypond
@end multitable



@emph{Modern style} means ``as is typeset in contemporary editions of
transcribed mensural music''.

@emph{Petrucci style} means ``inspired by printings published by the
famous engraver Petrucci (1466-1539)''.

@emph{Historic style} means ``as was typeset or written in historic
editions (other than those of Petrucci)''.

@emph{Editio XXX style} means ``as is/was printed in Editio XXX''.

Petrucci used C clefs with differently balanced left-side vertical
beams, depending on which staff line it is printed.

@seealso

In this manual: see @ref{Clef}.

@refbugs

The mensural g clef is mapped to the Petrucci g clef.



@node Ancient flags
@subsection Ancient flags

@cindex flags


Use the @code{flag-style} property of grob @internalsref{Stem} to
select ancient flags.  Besides the @code{default} flag style,
 only @code{mensural} style is supported

@lilypond[quote,fragment,raggedright,verbatim]
  \override Stem #'flag-style = #'mensural
  \override Stem #'thickness = #1.0
  \override NoteHead #'style = #'mensural
  \autoBeamOff
  c'8 d'8 e'8 f'8 c'16 d'16 e'16 f'16 c'32 d'32 e'32 f'32 s8
  c''8 d''8 e''8 f''8 c''16 d''16 e''16 f''16 c''32 d''32 e''32 f''32
@end lilypond

Note that the innermost flare of each mensural flag always is
vertically aligned with a staff line.

There is no particular flag style for neo-mensural notation.  Hence,
when typesetting the incipit of a transcribed piece of mensural
music, the default flag style should be used.  There are no flags in
Gregorian Chant notation.

@refbugs

The attachment of ancient flags to stems is slightly off due to a
change in early 2.3.x.

Vertically aligning each flag with a staff line assumes that stems
always end either exactly on or exactly in the middle between two
staff lines.  This may not always be true when using advanced layout
features of classical notation (which however are typically out of
scope for mensural notation).

@node Ancient time signatures
@subsection Ancient time signatures

@cindex time signatures


There is limited support for mensural time signatures.   The
glyphs are hard-wired to particular time fractions.  In other words,
to get a particular mensural signature glyph with the @code{\time n/m}
command, @code{n} and @code{m} have to be chosen according to the
following table

@lilypond[quote,raggedright]
\layout {
  indent = 0.0
  \context { \Staff
    \remove Staff_symbol_engraver
    \remove Clef_engraver
    \remove Time_signature_engraver
  }
} {
  \set Score.timing = ##f
  \set Score.barAlways = ##t
  s_\markup { "$\\backslash$time 4/4" }
  ^\markup { "       " \musicglyph #"timesig-neomensural4/4" }
  s
  s_\markup { "$\\backslash$time 2/2" }
  ^\markup { "       " \musicglyph #"timesig-neomensural2/2" }
  s
  s_\markup { "$\\backslash$time 6/4" }
  ^\markup { "       " \musicglyph #"timesig-neomensural6/4" }
  s
  s_\markup { "$\\backslash$time 6/8" }
  ^\markup { "       " \musicglyph #"timesig-neomensural6/8" }
  \break
  s_\markup { "$\\backslash$time 3/2" }
  ^\markup { "       " \musicglyph #"timesig-neomensural3/2" }
  s
  s_\markup { "$\\backslash$time 3/4" }
  ^\markup { "       " \musicglyph #"timesig-neomensural3/4" }
  s
  s_\markup { "$\\backslash$time 9/4" }
  ^\markup { "       " \musicglyph #"timesig-neomensural9/4" }
  s
  s_\markup { "$\\backslash$time 9/8" }
  ^\markup { "       " \musicglyph #"timesig-neomensural9/8" }
  \break
  s_\markup { "$\\backslash$time 4/8" }
  ^\markup { "       " \musicglyph #"timesig-neomensural4/8" }
  s
  s_\markup { "$\\backslash$time 2/4" }
  ^\markup { "       " \musicglyph #"timesig-neomensural2/4" }
}
@end lilypond

Use the @code{style} property of grob @internalsref{TimeSignature} to
select ancient time signatures.  Supported styles are
@code{neomensural} and @code{mensural}.  The above table uses the
@code{neomensural} style.  This style is appropriate for the
incipit of transcriptions of mensural pieces.  The @code{mensural}
style mimics the look of historical printings of the 16th century.

The following examples shows the differences in style,

@lilypond[raggedright,fragment,relative=1,quote]
{
  \fatText
  \time 2/2
  c1^\markup { \hspace #-2.0 \typewriter default }

  \override Staff.TimeSignature #'style = #'numbered  
  \time 2/2
  c1^\markup { \hspace #-2.0 \typewriter numbered }

  \override Staff.TimeSignature #'style = #'mensural
  \time 2/2
  c1^\markup { \hspace #-2.0 \typewriter mensural }
  
  \override Staff.TimeSignature #'style = #'neomensural
  \time 2/2
  c1^\markup { \hspace #-2.0 \typewriter neomensural }
  \override Staff.TimeSignature #'style = #'single-digit
  \time 2/2
  c1^\markup { \hspace #-2.0 \typewriter single-digit }
}
@end lilypond

@seealso

This manual: @ref{Time signature} gives a general introduction into
the use of time signatures.

@refbugs

Ratios of note durations do not change with the time signature.  For
example, the ratio of 1 brevis = 3 semibrevis (tempus perfectum) must
be made by hand, by setting

@example
  breveTP = #(ly:make-duration -1 0 3 2)
  @dots{}
  @{ c\breveTP f1 @}
@end example

@noindent
This sets @code{breveTP} to 3/2 times 2 = 3 times a whole note. 

The @code{old6/8alt} symbol (an alternate symbol for 6/8) is not
addressable with @code{\time}.  Use a @code{\markup} instead

@node Ancient articulations
@subsection Ancient articulations

@cindex articulations

In addition to the standard articulation signs described in section
@ref{Articulations}, articulation signs for ancient notation are
provided.  These are specifically designed for use with notation in
Editio Vaticana style.

@lilypond[quote,raggedright,verbatim]
\include "gregorian-init.ly"
\score {
  \context VaticanaVoice {
    \override TextScript #'font-family = #'typewriter
    \override TextScript #'font-shape = #'upright
    \override Script #'padding = #-0.1
    a4\ictus_"ictus" s1
    a4\circulus_"circulus" s1
    a4\semicirculus_"semicirculus" s1 s
    a4\accentus_"accentus" s1
    \[ a4_"episem" \episemInitium \pes b \flexa a \episemFinis \]
  }
}
@end lilypond

@refbugs

Some articulations are vertically placed too closely to the
correpsonding note heads.

@node Custodes
@subsection Custodes

@cindex custos
@cindex custodes

A @emph{custos} (plural: @emph{custodes}; Latin word for `guard') is a
symbol that appears at the end of a staff.  It anticipates the pitch
of the first note(s) of the following line thus helping the performer
to manage line breaks during performance.

Custodes were frequently used in music notation until the 17th
century.  Nowadays, they have survived only in a few particular forms
of musical notation such as contemporary editions of Gregorian chant
like the @emph{editio vaticana}.  There are different custos glyphs
used in different flavors of notational style.

For typesetting custodes, just put a @internalsref{Custos_engraver} into the
@internalsref{Staff} context when declaring the @code{\layout} block,
as shown in the following example

@example
\layout @{
  \context @{
    \Staff
    \consists Custos_engraver
    Custos \override #'style = #'mensural
  @}
@}
@end example

The result looks like this

@lilypond[quote,raggedright]
\score {
{
  a'1
  \override Staff.Custos #'style = #'mensural
  \break
  g'
}
\layout {
  \context { \Staff \consists Custos_engraver }
  }
}
@end lilypond

The custos glyph is selected by the @code{style} property.  The styles
supported are @code{vaticana}, @code{medicaea}, @code{hufnagel} and
@code{mensural}.  They are demonstrated in the following fragment

@lilypond[quote,raggedright,fragment]
\new Lyrics \lyricmode {
  \markup { \column <
    \typewriter "vaticana" 
    { " " \musicglyph #"custodes-vaticana-u0" }
  > }
  \markup { \column <
    \typewriter "medicaea"
    { " " \musicglyph #"custodes-medicaea-u0" }
  >}
  \markup { \column <
    \typewriter "hufnagel"
    { " " \musicglyph #"custodes-hufnagel-u0" }
  >}
  \markup { \column <
    \typewriter "mensural"
    { " " \musicglyph #"custodes-mensural-u0" }
  >}
}

@end lilypond

@seealso

Program reference: @internalsref{Custos}.

Examples: @inputfileref{input/@/regression,custos@/.ly}.


@node Divisiones
@subsection Divisiones

@cindex divisio
@cindex divisiones
@cindex finalis

A @emph{divisio} (plural: @emph{divisiones}; Latin word for
`division') is a staff context symbol that is used to structure
Gregorian music into phrases and sections.  The musical meaning of
@emph{divisio minima}, @emph{divisio maior} and @emph{divisio maxima}
can be characterized as short, medium and long pause, somewhat like
the breathmarks from @ref{Breath marks}.  The @emph{finalis} sign not
only marks the end of a chant, but is also frequently used within a
single antiphonal/responsorial chant to mark the end of each section.


To use divisiones, include the file @file{gregorian@/-init@/.ly}.  It
contains definitions that you can apply by just inserting
@code{\divisioMinima}, @code{\divisioMaior}, @code{\divisioMaxima},
and @code{\finalis} at proper places in the input.  Some editions use
@emph{virgula} or @emph{caesura} instead of divisio minima.
Therefore, @file{gregorian@/-init@/.ly} also defines @code{\virgula} and
@code{\caesura}

@lilypondfile[quote,raggedright]{divisiones.ly}

@refcommands

@cindex @code{\virgula}
@code{\virgula},
@cindex @code{\caesura}
@code{\caesura},
@cindex @code{\divisioMinima}
@code{\divisioMinima},
@cindex @code{\divisioMaior}
@code{\divisioMaior},
@cindex @code{\divisioMaxima}
@code{\divisioMaxima},
@cindex @code{\finalis}
@code{\finalis}.

@seealso

In this manual: @ref{Breath marks}.

Program reference: @internalsref{BreathingSign}, @internalsref{BreathingSignEvent}.

Examples: @inputfileref{input/@/test,divisiones@/.ly}.

@node Ligatures
@subsection Ligatures

@cindex Ligatures

@c TODO: Should double check if I recalled things correctly when I wrote
@c down the following paragraph by heart.

A ligature is a graphical symbol that represents at least two distinct
notes.  Ligatures originally appeared in the manuscripts of Gregorian
chant notation to denote ascending or descending sequences of notes.

Ligatures are entered by enclosing them in @code{\[} and @code{\]}.
Some ligature styles may need additional input syntax specific for
this particular type of ligature.  By default, the
@internalsref{LigatureBracket} engraver just puts a square bracket
above the ligature

@lilypond[quote,raggedright,verbatim]
\transpose c c' {
  \[ g c a f d' \]
  a g f
  \[ e f a g \]
}
@end lilypond

To select a specific style of ligatures, a proper ligature engraver
has to be added to the @internalsref{Voice} context, as explained in
the following subsections.   Only white mensural ligatures
are supported with certain limitations.



@refbugs

Ligatures need special spacing that has not yet been implemented.  As
a result, there is too much space between ligatures most of the time,
and line breaking often is unsatisfactory.  Also, lyrics do not
correctly align with ligatures.

Accidentals must not be printed within a ligature, but instead need to
be collected and printed in front of it.

Augmentum dots within ligatures are not handled correctly.


@menu
* White mensural ligatures::    
* Gregorian square neumes ligatures::  
@end menu

@node White mensural ligatures
@subsubsection White mensural ligatures

@cindex Mensural ligatures
@cindex White mensural ligatures

There is limited support for white mensural ligatures.  

To engrave white mensural ligatures, in the layout block the
@internalsref{Mensural_ligature_engraver} has to be put into the
@internalsref{Voice} context, and remove the
@internalsref{Ligature_bracket_engraver}

@example
\layout @{
  \context @{
    \Voice
    \remove Ligature_bracket_engraver
    \consists Mensural_ligature_engraver
  @}
@}
@end example

There is no additional input language to describe the shape of a
white mensural ligature.  The shape is rather determined solely from
the pitch and duration of the enclosed notes.  While this approach may
take a new user a while to get accustomed, it has the great advantage
that the full musical information of the ligature is known internally.
This is not only required for correct MIDI output, but also allows for
automatic transcription of the ligatures.

For example,

@example
  \set Score.timing = ##f
  \set Score.defaultBarType = "empty"
  \override NoteHead #'style = #'neomensural
  \override Staff.TimeSignature   #'style = #'neomensural
  \clef "petrucci-g"
  \[ g\longa c\breve a\breve f\breve d'\longa \]
  s4
  \[ e1 f1 a\breve g\longa \]
@end example
@lilypond[quote,raggedright]
\score {
  \transpose c c' {
    \set Score.timing = ##f
    \set Score.defaultBarType = "empty"
    \override NoteHead #'style = #'neomensural
    \override Staff.TimeSignature   #'style = #'neomensural
    \clef "petrucci-g"
    \[ g\longa c\breve a\breve f\breve d'\longa \]
    s4
    \[ e1 f1 a\breve g\longa \]
  }
  \layout {
    \context {
      \Voice
      \remove Ligature_bracket_engraver
      \consists Mensural_ligature_engraver
    }
  }
}
@end lilypond

Without replacing @internalsref{Ligature_bracket_engraver} with
@internalsref{Mensural_ligature_engraver}, the same music transcribes
to the following

@lilypond[quote,raggedright]
\transpose c c' {
  \set Score.timing = ##f
  \set Score.defaultBarType = "empty"
  \override NoteHead #'style = #'neomensural
  \override Staff.TimeSignature   #'style = #'neomensural
  \clef "petrucci-g"
  \[ g\longa c\breve a\breve f\breve d'\longa \]
  s4
  \[ e1 f1 a\breve g\longa \]
}
@end lilypond

@refbugs

The implementation is experimental.  It may output strange warnings,
incorrect results, and might even crash on more complex ligatures.

@node Gregorian square neumes ligatures
@subsubsection Gregorian square neumes ligatures

@cindex Square neumes ligatures
@cindex Gregorian square neumes ligatures

There is limited support for Gregorian square neumes notation
(following the style of the Editio Vaticana).  Core ligatures can
already be typeset, but essential issues for serious typesetting are
still lacking, such as (among others) horizontal alignment of multiple
ligatures, lyrics alignment and proper accidentals handling.


The following table contains the extended neumes table of the 2nd
volume of the Antiphonale Romanum (@emph{Liber Hymnarius}), published
1983 by the monks of Solesmes.

@multitable @columnfractions .4 .2 .2 .2

@item
@b{Neuma aut@*
Neumarum Elementa}
@tab
@b{Figurae@*
Rectae}
@tab
@b{Figurae@*
Liquescentes@*
Auctae}
@tab
@b{Figurae@*
Liquescentes@*
Deminutae}

@c TODO: \layout block is identical in all of the below examples.
@c Therefore, it should somehow be included rather than duplicated all
@c the time. --jr

@c why not make identifiers in ly/engraver-init.ly? --hwn

@c Because it's just used to typeset plain notes without
@c a staff for demonstration purposes rather than something
@c special of Gregorian chant notation. --jr

@item
@code{1. Punctum}
@tab
@lilypond[staffsize=26,linewidth=1.5\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Punctum
    \[ b \]
    \noBreak s^\markup {"a"} \noBreak

    % Punctum Inclinatum
    \[ \inclinatum b \]
    \noBreak s^\markup {"b"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@lilypond[staffsize=26,linewidth=2.5\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Punctum Auctum Ascendens
    \[ \auctum \ascendens b \]
    \noBreak s^\markup {"c"} \noBreak

    % Punctum Auctum Descendens
    \[ \auctum \descendens b \]
    \noBreak s^\markup {"d"} \noBreak

    % Punctum Inclinatum Auctum
    \[ \inclinatum \auctum b \]
    \noBreak s^\markup {"e"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Punctum Inclinatum Parvum
    \[ \inclinatum \deminutum b \]
    \noBreak s^\markup {"f"}
  }
\layout { \neumeDemoLayout }}
@end lilypond

@item
@code{2. Virga}
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Virga
    \[ \virga b \]
    \noBreak s^\markup {"g"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@tab

@item
@code{3. Apostropha vel Stropha}
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Stropha
    \[ \stropha b \]
    \noBreak s^\markup {"h"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Stropha Aucta
    \[ \stropha \auctum b \]
    \noBreak s^\markup {"i"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab

@item
@code{4. Oriscus}
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Oriscus
    \[ \oriscus b \]
    \noBreak s^\markup {"j"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@tab

@item
@code{5. Clivis vel Flexa}
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Clivis vel Flexa
    \[ b \flexa g \]
    s^\markup {"k"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@lilypond[staffsize=26,linewidth=2.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Clivis Aucta Descendens
    \[ b \flexa \auctum \descendens g \]
    \noBreak s^\markup {"l"} \noBreak

    % Clivis Aucta Ascendens
    \[ b \flexa \auctum \ascendens g \]
    \noBreak s^\markup {"m"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Cephalicus
    \[ b \flexa \deminutum g \]
    s^\markup {"n"}
  }
\layout { \neumeDemoLayout }}
@end lilypond

@item
@code{6. Podatus vel Pes}
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Podatus vel Pes
    \[ g \pes b \]
    s^\markup {"o"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@lilypond[staffsize=26,linewidth=2.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Pes Auctus Descendens
    \[ g \pes \auctum \descendens b \]
    \noBreak s^\markup {"p"} \noBreak

    % Pes Auctus Ascendens
    \[ g \pes \auctum \ascendens b \]
    \noBreak s^\markup {"q"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Epiphonus
    \[ g \pes \deminutum b \]
    s^\markup {"r"}
  }
\layout { \neumeDemoLayout }}
@end lilypond

@item
@code{7. Pes Quassus}
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Pes Quassus
    \[ \oriscus g \pes \virga b \]
    s^\markup {"s"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Pes Quassus Auctus Descendens
    \[ \oriscus g \pes \auctum \descendens b \]
    s^\markup {"t"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab

@item
@code{8. Quilisma Pes}
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Quilisma Pes
    \[ \quilisma g \pes b \]
    s^\markup {"u"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Quilisma Pes Auctus Descendens
    \[ \quilisma g \pes \auctum \descendens b \]
    s^\markup {"v"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab

@item
@code{9. Podatus Initio Debilis}
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Pes Initio Debilis
    \[ \deminutum g \pes b \]
    s^\markup {"w"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Pes Auctus Descendens Initio Debilis
    \[ \deminutum g \pes \auctum \descendens b \]
    s^\markup {"x"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab

@item
@code{10. Torculus}
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Torculus
    \[ a \pes b \flexa g \]
    s^\markup {"y"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Torculus Auctus Descendens
    \[ a \pes b \flexa \auctum \descendens g \]
    s^\markup {"z"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Torculus Deminutus
    \[ a \pes b \flexa \deminutum g \]
    s^\markup {"A"}
  }
\layout { \neumeDemoLayout }}
@end lilypond

@item
@code{11. Torculus Initio Debilis}
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Torculus Initio Debilis
    \[ \deminutum a \pes b \flexa g \]
    s^\markup {"B"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Torculus Auctus Descendens Initio Debilis
    \[ \deminutum a \pes b \flexa \auctum \descendens g \]
    s^\markup {"C"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Torculus Deminutus Initio Debilis
    \[ \deminutum a \pes b \flexa \deminutum g \]
    s^\markup {"D"}
  }
\layout { \neumeDemoLayout }}
@end lilypond

@item
@code{12. Porrectus}
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Porrectus
    \[ a \flexa g \pes b \]
    s^\markup {"E"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Porrectus Auctus Descendens
    \[ a \flexa g \pes \auctum \descendens b \]
    s^\markup {"F"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Porrectus Deminutus
    \[ a \flexa g \pes \deminutum b \]
    s^\markup {"G"}
  }
\layout { \neumeDemoLayout }}
@end lilypond

@item
@code{13. Climacus}
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Climacus
    \[ \virga b \inclinatum a \inclinatum g \]
    s^\markup {"H"}
  }
  \layout { \neumeDemoLayout }
}
@end lilypond
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Climacus Auctus
    \[ \virga b \inclinatum a \inclinatum \auctum g \]
    s^\markup {"I"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Climacus Deminutus
    \[ \virga b \inclinatum a \inclinatum \deminutum g \]
    s^\markup {"J"}
  }
\layout { \neumeDemoLayout }}
@end lilypond

@item
@code{14. Scandicus}
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Scandicus
    \[ g \pes a \virga b \]
    s^\markup {"K"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Scandicus Auctus Descendens
    \[ g \pes a \pes \auctum \descendens b \]
    s^\markup {"L"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Scandicus Deminutus
    \[ g \pes a \pes \deminutum b \]
    s^\markup {"M"}
  }
\layout { \neumeDemoLayout }}
@end lilypond

@item
@code{15. Salicus}
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Salicus
    \[ g \oriscus a \pes \virga b \]
    s^\markup {"N"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Salicus Auctus Descendens
    \[ g \oriscus a \pes \auctum \descendens b \]
    s^\markup {"O"}
  }
\layout { \neumeDemoLayout }}
@end lilypond
@tab

@item
@code{16. Trigonus}
@tab
@lilypond[staffsize=26,linewidth=1.0\cm]
\include "gregorian-init.ly"
\score {
  \transpose c c' {
    % Trigonus
    \[ \stropha b \stropha b \stropha a \]
    s^\markup {"P"}
  }
  \layout { \neumeDemoLayout }
}
@end lilypond
@tab
@tab

@end multitable


Unlike most other neumes notation systems, the input language for
neumes does not reflect the typographical appearance, but is designed
to focus on musical meaning.  For example, @code{\[ a \pes b
\flexa g \]} produces a Torculus consisting of three Punctum heads,
while @code{\[ a \flexa g \pes b \]} produces a Porrectus with a
curved flexa shape and only a single Punctum head.  There is no
command to explicitly typeset the curved flexa shape; the decision of
when to typeset a curved flexa shape is based on the musical
input.  The idea of this approach is to separate the musical aspects
of the input from the notation style of the output.  This way, the
same input can be reused to typeset the same music in a different
style of Gregorian chant notation.

The following table shows the code fragments that produce the
ligatures in the above neumes table.  The letter in the first column
in each line of the below table indicates to which ligature in the
above table it refers.  The second column gives the name of the
ligature.  The third column shows the code fragment that produces this
ligature, using @code{g}, @code{a} and @code{b} as example pitches.

@multitable @columnfractions .02 .31 .67
@item
@b{#}
@tab
@b{Name}
@tab
@b{Input Language}

@item
a
@tab
Punctum
@tab
@code{\[ b \]}

@item
b
@tab
Punctum Inclinatum
@tab
@code{\[ \inclinatum b \]}

@item
c
@tab
Punctum Auctum@*
Ascendens
@tab
@code{\[ \auctum \ascendens b \]}

@item
d
@tab
Punctum Auctum@*
Descendens
@tab
@code{\[ \auctum \descendens b \]}

@item
e
@tab
Punctum Inclinatum@*
Auctum
@tab
@code{\[ \inclinatum \auctum b \]}

@item
f
@tab
Punctum Inclinatum@*
Parvum @tab
@code{\[ \inclinatum \deminutum b \]}

@item
g
@tab
Virga
@tab
@code{\[ \virga b \]}

@item
h
@tab
Stropha
@tab
@code{\[ \stropha b \]}

@item
i
@tab
Stropha Aucta
@tab
@code{\[ \stropha \auctum b \]}

@item
j
@tab
Oriscus
@tab
@code{\[ \oriscus b \]}

@item
k
@tab
Clivis vel Flexa
@tab
@code{\[ b \flexa g \]}

@item
l
@tab
Clivis Aucta@*
Descendens
@tab
@code{\[ b \flexa \auctum \descendens g \]}

@item
m
@tab
Clivis Aucta@*
Ascendens
@tab
@code{\[ b \flexa \auctum \ascendens g \]}

@item
n
@tab
Cephalicus
@tab
@code{\[ b \flexa \deminutum g \]}

@item
o
@tab
Podatus vel Pes
@tab
@code{\[ g \pes b \]}

@item
p
@tab
Pes Auctus@*
Descendens
@tab
@code{\[ g \pes \auctum \descendens b \]}

@item
q
@tab
Pes Auctus@*
Ascendens
@tab
@code{\[ g \pes \auctum \ascendens b \]}

@item
r
@tab
Epiphonus
@tab
@code{\[ g \pes \deminutum b \]}

@item
s
@tab
Pes Quassus
@tab
@code{\[ \oriscus g \pes \virga b \]}

@item
t
@tab
Pes Quassus@*
Auctus Descendens @tab
@code{\[ \oriscus g \pes \auctum \descendens b \]}

@item
u
@tab
Quilisma Pes
@tab
@code{\[ \quilisma g \pes b \]}

@item
v
@tab
Quilisma Pes@*
Auctus Descendens
@tab
@code{\[ \quilisma g \pes \auctum \descendens b \]}

@item
w
@tab
Pes Initio Debilis
@tab
@code{\[ \deminutum g \pes b \]}

@item
x
@tab
Pes Auctus Descendens@*
Initio Debilis
@tab
@code{\[ \deminutum g \pes \auctum \descendens b \]}

@item
y
@tab
Torculus
@tab
@code{\[ a \pes b \flexa g \]}

@item
z
@tab
Torculus Auctus@*
Descendens
@tab
@code{\[ a \pes b \flexa \auctum \descendens g \]}

@item
A
@tab
Torculus Deminutus
@tab
@code{\[ a \pes b \flexa \deminutum g \]}

@item
B
@tab
Torculus Initio Debilis
@tab
@code{\[ \deminutum a \pes b \flexa g \]}

@item
C
@tab
Torculus Auctus@*
Descendens Initio Debilis
@tab
@code{\[ \deminutum a \pes b \flexa \auctum \descendens g \]}

@item
D
@tab
Torculus Deminutus@*
Initio Debilis
@tab
@code{\[ \deminutum a \pes b \flexa \deminutum g \]}

@item
E
@tab
Porrectus
@tab
@code{\[ a \flexa g \pes b \]}

@item
F
@tab
Porrectus Auctus@*
Descendens
@tab
@code{\[ a \flexa g \pes \auctum \descendens b \]}

@item
G
@tab
Porrectus Deminutus
@tab
@code{\[ a \flexa g \pes \deminutum b \]}

@item
H
@tab
Climacus
@tab
@code{\[ \virga b \inclinatum a \inclinatum g \]}

@item
I
@tab
Climacus Auctus
@tab
@code{\[ \virga b \inclinatum a \inclinatum \auctum g \]}

@item
J
@tab
Climacus Deminutus
@tab
@code{\[ \virga b \inclinatum a \inclinatum \deminutum g \]}

@item
K
@tab
Scandicus
@tab
@code{\[ g \pes a \virga b \]}

@item
L
@tab
Scandicus Auctus@*
Descendens
@tab
@code{\[ g \pes a \pes \auctum \descendens b \]}

@item
M
@tab
Scandicus Deminutus
@tab
@code{\[ g \pes a \pes \deminutum b \]}

@item
N
@tab
Salicus
@tab
@code{\[ g \oriscus a \pes \virga b \]}

@item
O
@tab
Salicus Auctus Descendens
@tab
@code{\[ g \oriscus a \pes \auctum \descendens b \]}

@item
P
@tab
Trigonus
@tab
@code{\[ \stropha b \stropha b \stropha a \]}
@end multitable

@refcommands

The following head prefixes are supported

@cindex @code{\virga}
@code{\virga},
@cindex @code{\stropha}
@code{\stropha},
@cindex @code{\inclinatum}
@code{\inclinatum},
@cindex @code{\auctum}
@code{\auctum},
@cindex @code{\descendens}
@code{\descendens},
@cindex @code{\ascendens}
@code{\ascendens},
@cindex @code{\oriscus}
@code{\oriscus},
@cindex @code{\quilisma}
@code{\quilisma},
@cindex @code{\deminutum}
@code{\deminutum}.

Head prefixes can be accumulated, though restrictions apply.  For
example, either @code{\descendens} or @code{\ascendens} can be applied
to a head, but not both to the same head.

@cindex @code{\pes}
@cindex @code{\flexa}
Two adjacent heads can be tied together with the @code{\pes} and
@code{\flexa} infix commands for a rising and falling line of melody,
respectively.



@node Gregorian Chant contexts
@subsection Gregorian Chant contexts

@cindex VaticanaVoiceContext
@cindex VaticanaStaffContext

The predefined @code{VaticanaVoiceContext} and
@code{VaticanaStaffContext} can be used to engrave a piece of
Gregorian Chant in the style of the Editio Vaticana.  These contexts
initialize all relevant context properties and grob properties to
proper values, so you can immediately go ahead entering the chant, as
the following excerpt demonstrates

@lilypond[quote,raggedright,verbatim]
\include "gregorian-init.ly"
\score {
  <<
    \context VaticanaVoice = "cantus" {
      \override Score.BarNumber #'transparent = ##t {
        \[ c'\melisma c' \flexa a \]
        \[ a \flexa \deminutum g\melismaEnd \]
        f \divisioMinima
        \[ f\melisma \pes a c' c' \pes d'\melismaEnd \]
        c' \divisioMinima \break
        \[ c'\melisma c' \flexa a \]
        \[ a \flexa \deminutum g\melismaEnd \] f \divisioMinima
      }
    }
    \lyricsto "cantus" \new Lyrics {
      San- ctus, San- ctus, San- ctus
    }
  >>
}
@end lilypond


@node Mensural contexts
@subsection Mensural contexts

@cindex MensuralVoiceContext
@cindex MensuralStaffContext

The predefined @code{MensuralVoiceContext} and
@code{MensuralStaffContext} can be used to engrave a piece in mensural
style.  These contexts initialize all relevant context properties and
grob properties to proper values, so you can immediately go ahead
entering the chant, as the following excerpt demonstrates

@lilypond[quote,raggedright,verbatim]
\score {
  <<
    \context MensuralVoice = "discantus" \transpose c c' {
      \override Score.BarNumber #'transparent = ##t {
        c'1\melisma bes a g\melismaEnd
        f\breve
        \[ f1\melisma a c'\breve d'\melismaEnd \]
        c'\longa
        c'\breve\melisma a1 g1\melismaEnd
        fis\longa^\signumcongruentiae
      }
    }
    \lyricsto "discantus" \new Lyrics {
      San -- ctus, San -- ctus, San -- ctus
    }
  >>
}
@end lilypond


@node Figured bass
@subsection Figured bass

@cindex Basso continuo

@c TODO: musicological blurb about FB


LilyPond has limited support for figured bass

@lilypond[quote,raggedright,verbatim,fragment]
<<
  \context Voice  { \clef bass dis4  c d ais }
  \context FiguredBass \figuremode {
    < 6 >4 < 7 >8 < 6+ [_!] >
    < 6 >4 <6 5 [3+] >
  }
>>
@end lilypond

The support for figured bass consists of two parts: there is an input
mode, introduced by @code{\figuremode}, where you can enter bass figures
as numbers, and there is a context called @internalsref{FiguredBass} that
takes care of making @internalsref{BassFigure} objects.

In figures input mode, a group of bass figures is delimited by
@code{<} and @code{>}.  The duration is entered after the @code{>}
@example
<4 6>
@end example
@lilypond[quote,raggedright,fragment]
\context FiguredBass
\figuremode { <4 6> }
@end lilypond

Accidentals are added when you append @code{-}, @code{!}  and @code{+}
to the numbers

@example
<4- 6+ 7!>
@end example
@lilypond[quote,raggedright,fragment]
  \context FiguredBass
  \figuremode { <4- 6+ 7!> }
@end lilypond

Spaces or dashes may be inserted by using @code{_}.  Brackets are
introduced with @code{[} and @code{]}

@example
< [4 6] 8 [_! 12]>
@end example
@lilypond[quote,raggedright,fragment]
  \context FiguredBass
  \figuremode { < [4 6] 8 [_! 12]> }
@end lilypond

Although the support for figured bass may superficially resemble chord
support, it works much simpler.  The @code{\figuremode} mode simply
stores the numbers , and @internalsref{FiguredBass} context prints
them as entered.  There is no conversion to pitches, and no
realizations of the bass are played in the MIDI file.

Internally, the code produces markup texts.  You can use any of the
markup text properties to override formatting.  For example, the
vertical spacing of the figures may be set with @code{baseline-skip}.

@seealso

Program reference: @internalsref{BassFigureEvent} music, @internalsref{BassFigure} object, 
and @internalsref{FiguredBass} context.

@refbugs

Slash notation for alterations is not supported.

@node Contemporary notation
@section Contemporary notation

In the 20th century, composers have greatly expanded the musical
vocabulary.  With this expansion, many innovations in musical notation
have been tried.  The book ``Music Notation in the 20th century'' by
Kurt Stone gives a comprehensive overview (see @ref{Literature
list}).  In general, the use of new, innovative notation makes a piece
harder to understand and perform and its use should therefore be
avoided.  For this reason, support for contemporary notation in
LilyPond is limited.


@menu
* Polymetric notation::         
* Clusters::                    
* Special fermatas::            
* Feathered beams::             
@end menu

@node Polymetric notation
@subsection Polymetric notation

Double time signatures are not supported explicitly, but they can be
faked.  In the next example, the markup for the time signature is
created with a markup text.  This markup text is inserted in the
@internalsref{TimeSignature} grob.

@lilypond[verbatim,raggedright]

% create 2/4 + 5/8
tsMarkup =\markup  {
  \number { 
    \column < "2" "4" >
    \musicglyph #"scripts-stopped" 
    \bracket \column < "5" "8" >
  }
}

{
  \override Staff.TimeSignature #'print-function = #Text_interface::print
  \override Staff.TimeSignature #'text = #tsMarkup
  \time 3/2
  c'2 \bar ":" c'4 c'4.
}
@end lilypond

Each staff can also have its own time signature.  This is done by
moving the @internalsref{Timing_engraver} to @internalsref{Staff}
context.

@verbatim
\layout{
  \context{ \Score \remove "Timing_engraver" }
  \context{ \Staff \consists "Timing_engraver" }
}       
@end verbatim


Now, each staff has its own time signature.
@verbatim
<<
  \new Staff {
    \time 3/4
    c4 c c | c c c |
  }
  \new Staff {
    \time 2/4
    c4 c | c c | c c
  }
  \new Staff {
    \time 3/8
    c4. c8 c c c4. c8 c c
  }
>>
@end verbatim

@lilypond[quote,raggedright]
\layout{
  \context{ \Score \remove "Timing_engraver" }
  \context{ \Staff \consists "Timing_engraver" }
}       

\relative c'  <<
  \new Staff {
    \time 3/4
    c4 c c | c c c |
  }
  \new Staff {
    \time 2/4
    c4 c | c c | c c
  }
  \new Staff {
    \time 3/8
    c4. c8 c c c4. c8 c c
  }
>>
@end lilypond


A different form of polymetric notation is where note lengths have
different values across staves.

This notation can be created by setting a common time signature for
each staff but replacing it manually using
@code{timeSignatureFraction} to the desired fraction.  Then the printed
durations in each staff are scaled to the common time signature.
The latter is done with @code{\compressmusic}, which is similar to
@code{\times}, but does not create a tuplet bracket.


In this example, music with the time signatures of 3/4, 9/8 and 10/8 are
used in parallel.  In the second staff, shown durations are multiplied by 
2/3, so that 2/3 * 9/8 = 3/4, and in the third staff, shown durations are 
multiplied by 3/5, so that 3/5 * 10/8 = 3/4.

@lilypond[raggedright,verbatim,fragment]
\relative c' { <<
  \new Staff {
    \time 3/4
    c4 c c | c c c |
  }
  \new Staff {
    \time 3/4
    \set Staff.timeSignatureFraction = #'(9 . 8)
    \compressmusic #'(2 . 3)
      \repeat unfold 6 { c8[ c c] }
  }
  \new Staff {
    \time 3/4
    \set Staff.timeSignatureFraction = #'(10 . 8)
    \compressmusic #'(3 . 5) {
      \repeat unfold 2 { c8[ c c] }
      \repeat unfold 2 { c8[  c] }
      | c4. c4. \times 2/3 { c8 c c } c4
    }
  }
>> }
@end lilypond




@refbugs

When using different time signatures in parallel, the spacing is
aligned vertically, but bar lines distort the regular spacing.



@node Clusters
@subsection Clusters

@cindex cluster

A cluster indicates a continuous range of pitches to be played.  They
can be denoted as the envelope of a set of notes.  They are entered by
applying the function @code{makeClusters} to a sequence of
chords, e.g.
@c
@lilypond[quote,raggedright,relative=2,fragment,verbatim]
  \makeClusters { <c e > <b f'> }
@end lilypond

The following example (from
@inputfileref{input/@/regression,cluster@/.ly}) shows what the result
looks like

@lilypondfile[raggedright,quote]{cluster.ly}

Ordinary notes and clusters can be put together in the same staff,
even simultaneously.  In such a case no attempt is made to
automatically avoid collisions between ordinary notes and clusters.

@seealso

Program reference: @internalsref{ClusterSpanner},
@internalsref{ClusterSpannerBeacon},
@internalsref{Cluster_spanner_engraver}, and
@internalsref{ClusterNoteEvent}.

Examples: @inputfileref{input/@/regression,cluster@/.ly}.

@refbugs

Music expressions like @code{<< @{ g8 e8 @} a4 >>} are not printed
accurately.  Use @code{<g a>8 <e a>8} instead.



@node Special fermatas
@subsection Special fermatas

@cindex fermatas, special

In contemporary music notation, special fermata symbols denote breaks
of differing lengths.  The following fermatas are supported

@lilypond[quote,raggedright]
<<
  \oldaddlyrics  {
    b'2
    ^\shortfermata
    _\shortfermata
    r

    b'
    ^\fermata
    _\fermata
    r

    b'
    ^\longfermata
    _\longfermata
    r

    b'
    ^\verylongfermata
    _\verylongfermata
    r
  }
  \context Lyrics \lyricmode {
    \override LyricText #'font-family = #'typewriter
    "shortfermata" "fermata"  "longfermata" "verylongfermata"
  }
>>
@end lilypond

See @ref{Articulations} for general instructions how to apply scripts
such as fermatas to notes.

@node Feathered beams
@subsection Feathered beams

Feathered beams are not supported natively, but they can be faked by
forcing two beams to overlap.  Here is an example,

@c don't change  relative setting witout changing positions!
@lilypond[raggedright,relative=1,fragment,verbatim]
\new Staff <<
  \new Voice
  {
    \stemUp
    \once \override Voice.Beam #'positions = #'(0 . 0.5)
    c8[ c c c c ]
  }
  \new Voice {
    \stemUp
    \once \override Voice.Beam #'positions = #'(0 . -0.5) 
    c[ c c c c]
  }
>>
@end lilypond



@node Educational use
@section Educational use

With the amount of control that LilyPond offers, one can make great
teaching tools in addition to great musical scores.

@menu
* Balloon help::                
* Blank music sheet::           
* Hidden notes::     
* Easy Notation note heads::    
@end menu

@node Balloon help
@subsection Balloon help

Elements of notation can be marked and named with the help of a square
balloon.  The primary purpose of this feature is to explain notation.

The following example demonstrates its use.

@lilypond[quote,verbatim,fragment,raggedright,relative=2]
\context Voice {
  \applyoutput
    #(add-balloon-text 'NoteHead "heads, or tails?"
    '(1 . -3))
  c8
}
@end lilypond

@noindent
The function @code{add-balloon-text} takes the name of a grob, the
label to print, and the position where to put the label relative to 
the object.  In the above example, the text ``heads or tails?'' ends 
3 spaces below and 1 space to the right of the marked head.

@cindex balloon
@cindex notation, explaining

@seealso

Program reference: @internalsref{text-balloon-interface}.

Examples: @inputfileref{input/@/regression,balloon@/.ly}.




@node Blank music sheet
@subsection Blank music sheet

A blank music sheet can be produced also by using invisible notes, and
removing @code{Bar_number_engraver}.


@lilypond[]
emptymusic =  {
  \repeat unfold 2 % Change this for more lines. 
  { s1\break }
  \bar "|."
}
\new Score \with {
  \override TimeSignature #'transparent = ##t
  defaultBarType = #""
  \remove Bar_number_engraver
} <<
  \context Staff \emptymusic
  \context TabStaff \emptymusic
>>
@end lilypond


@node Hidden notes
@subsection Hidden notes

@cindex Hidden notes
@cindex Invisible notes
@cindex Transparent notes

Hidden (or invisible or transparent) notes can be useful in preparing theory
or composition exercises.

@lilypond[quote,raggedright,verbatim,relative=2,fragment]
  c4 d4 
  \hideNotes
  e4 f4
  \unHideNotes
  g4 a 
@end lilypond

Hidden notes are also great for performing weird tricks.  For example,
slurs cannot be attached to rests or spacer rests, but you may with
to include that in your score -- string instruments use this notation
when doing pizzicato to indicate that the note should ring for as long
as possible.

@lilypond[quote,raggedright,verbatim,relative=0,fragment]
  \clef bass
  << {
    c4^"pizz"( \hideNotes c)
    \unHideNotes c( \hideNotes c)
  } {
    s4 r s r
  } >>
@end lilypond


@node Easy Notation note heads
@subsection Easy Notation note heads

@cindex easy notation
@cindex Hal Leonard

The `easy play' note head includes a note name inside the head.  It is
used in music for beginners

@lilypond[quote,raggedright,verbatim,fragment,staffsize=26]
  \setEasyHeads
  c'2 e'4 f' | g'1
@end lilypond

The command @code{\setEasyHeads} overrides settings for the
@internalsref{NoteHead} object.  To make the letters readable, it has
to be printed in a large font size.  To print with a larger font, see
@ref{Setting global staff size}.

@refcommands

@cindex @code{\setEasyHeads}
@code{\setEasyHeads}