X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=flower%2Frational.cc;h=a0c0d22410e235726eeee037b760fee1f7dcaef9;hb=b05241299d5e20c07676430c516d3ed0d35a8e9a;hp=a50228330b16c59bc80004b420feba9c8bc22274;hpb=bb36bac02a64770871780231ecc709cb18b20932;p=lilypond.git

diff --git a/flower/rational.cc b/flower/rational.cc
index a50228330b..a0c0d22410 100644
--- a/flower/rational.cc
+++ b/flower/rational.cc
@@ -1,43 +1,43 @@
 /*
   rational.cc -- implement Rational
-  
+
   source file of the Flower Library
 
-  (c)  1997--2000 Han-Wen Nienhuys <hanwen@cs.uu.nl>
+  (c) 1997--2006 Han-Wen Nienhuys <hanwen@xs4all.nl>
 */
-#include <math.h>
-#include <stdlib.h>
+
 #include "rational.hh"
-#include "string.hh"
-#include "string-convert.hh"  
-#include "libc-extension.hh"
 
-Rational::operator bool () const
-{
-  return sign_;
-}
+#include <cmath>
+#include <cstdlib>
+using namespace std;
+
+#include "string-convert.hh"
+#include "libc-extension.hh"
 
-Rational::operator int () const
+Rational::operator double () const
 {
-  return sign_ * num_ / den_;
+  return ((double)sign_) * num_ / den_;
 }
 
-Rational::operator double () const
+Rational::operator bool () const
 {
-  return (double)sign_ * num_ / den_;
+  return sign_ && num_;
 }
 
+#ifdef STREAM_SUPPORT
 ostream &
 operator << (ostream &o, Rational r)
 {
-  o <<  r.str ();
+  o << r.string ();
   return o;
 }
+#endif
 
 Rational
 Rational::trunc_rat () const
 {
-  return Rational(num_ - (num_ % den_), den_);
+  return Rational (num_ - (num_ % den_), den_);
 }
 
 Rational::Rational ()
@@ -54,7 +54,14 @@ Rational::Rational (int n, int d)
   normalise ();
 }
 
-static
+Rational::Rational (int n)
+{
+  sign_ = ::sign (n);
+  num_ = abs (n);
+  den_ = 1;
+}
+
+static inline
 int gcd (int a, int b)
 {
   int t;
@@ -66,22 +73,16 @@ int gcd (int a, int b)
   return b;
 }
 
-static
-int lcm (int a, int b)
-{
-  return abs (a*b / gcd (a,b));
-}
-
 void
 Rational::set_infinite (int s)
 {
-  sign_ = ::sign (s) * 2; 
+  sign_ = ::sign (s) * 2;
 }
 
 Rational
 Rational::operator - () const
 {
-  Rational r(*this);
+  Rational r (*this);
   r.negate ();
   return r;
 }
@@ -109,31 +110,31 @@ Rational::normalise ()
     {
       den_ = 1;
       num_ = 0;
-      return ;
     }
-  if (!den_)
-    sign_ = 2;
-  if (!num_)
-    sign_ = 0;
-
-  int g = gcd (num_ , den_);
+  else if (!den_)
+    {
+      sign_ = 2;
+      num_ = 1;
+    }
+  else if (!num_)
+    {
+      sign_ = 0;
+      den_ = 1;
+    }
+  else
+    {
+      int g = gcd (num_, den_);
 
-  num_ /= g;
-  den_ /= g;
+      num_ /= g;
+      den_ /= g;
+    }
 }
-
 int
 Rational::sign () const
 {
   return ::sign (sign_);
 }
 
-bool
-Rational::infty_b () const
-{
-  return abs (sign_) > 1;
-}
-
 int
 Rational::compare (Rational const &r, Rational const &s)
 {
@@ -141,51 +142,50 @@ Rational::compare (Rational const &r, Rational const &s)
     return -1;
   else if (r.sign_ > s.sign_)
     return 1;
-  else if (r.infty_b ())
+  else if (r.is_infinity ())
     return 0;
-
-  return  (r - s).sign ();
+  else if (r.sign_ == 0)
+    return 0;
+  return r.sign_ * ::sign (int (r.num_ * s.den_) - int (s.num_ * r.den_));
 }
 
 int
 compare (Rational const &r, Rational const &s)
 {
-  return Rational::compare (r, s );
+  return Rational::compare (r, s);
 }
 
 Rational &
 Rational::operator %= (Rational r)
 {
-  *this = r.mod_rat (r);
+  *this = mod_rat (r);
   return *this;
 }
 
 Rational &
 Rational::operator += (Rational r)
 {
-  if (infty_b ())
+  if (is_infinity ())
     ;
-  else if (r.infty_b ())
-    {
-      *this = r;
-    }
-  else 
+  else if (r.is_infinity ())
+    *this = r;
+  else
     {
-      int n = sign_ * num_ *r.den_ + r.sign_ * den_ * r.num_;
-      int d = den_ * r.den_;
-      sign_ =  ::sign (n) * ::sign(d);
+      int lcm = (den_ / gcd (r.den_, den_)) * r.den_;
+      int n = sign_ * num_ * (lcm / den_) + r.sign_ * r.num_ * (lcm / r.den_);
+      int d = lcm;
+      sign_ = ::sign (n) * ::sign (d);
       num_ = abs (n);
       den_ = abs (d);
       normalise ();
     }
   return *this;
 }
-    
 
 /*
   copied from libg++ 2.8.0
- */ 
-Rational::Rational(double x)
+*/
+Rational::Rational (double x)
 {
   if (x != 0.0)
     {
@@ -193,7 +193,7 @@ Rational::Rational(double x)
       x *= sign_;
 
       int expt;
-      double mantissa = frexp(x, &expt);
+      double mantissa = frexp (x, &expt);
 
       const int FACT = 1 << 20;
 
@@ -207,7 +207,7 @@ Rational::Rational(double x)
 
       num_ = (unsigned int) (mantissa * FACT);
       den_ = (unsigned int) FACT;
-      normalise ();      
+      normalise ();
       if (expt < 0)
 	den_ <<= -expt;
       else
@@ -218,17 +218,16 @@ Rational::Rational(double x)
     {
       num_ = 0;
       den_ = 1;
-      sign_ =0;
+      sign_ = 0;
       normalise ();
     }
 }
 
-
 void
 Rational::invert ()
 {
   int r (num_);
-  num_  = den_;
+  num_ = den_;
   den_ = r;
 }
 
@@ -236,8 +235,8 @@ Rational &
 Rational::operator *= (Rational r)
 {
   sign_ *= ::sign (r.sign_);
-  if (r.infty_b ())
-    {	
+  if (r.is_infinity ())
+    {
       sign_ = sign () * 2;
       goto exit_func;
     }
@@ -249,7 +248,7 @@ Rational::operator *= (Rational r)
  exit_func:
   return *this;
 }
-  
+
 Rational &
 Rational::operator /= (Rational r)
 {
@@ -263,39 +262,42 @@ Rational::negate ()
   sign_ *= -1;
 }
 
-Rational&
+Rational &
 Rational::operator -= (Rational r)
 {
   r.negate ();
   return (*this += r);
 }
 
-/*
-  be paranoid about overiding libg++ stuff
- */
-Rational &
-Rational::operator = (Rational const &r)
+string
+Rational::to_string () const
 {
-  copy (r);
-  return *this;
-}
-
-String
-Rational::str () const
-{
-  if (infty_b ())
+  if (is_infinity ())
     {
-      String s (sign_ > 0 ? "" : "-" );
-      return String (s + "infinity");
+      string s (sign_ > 0 ? "" : "-");
+      return string (s + "infinity");
     }
-  String s = to_str (num ());
+
+  string s = ::to_string (num ());
   if (den () != 1 && num ())
-    s += "/" + to_str (den ());
+    s += "/" + ::to_string (den ());
   return s;
 }
 
+int
+Rational::to_int () const
+{
+  return (int) num () / den ();
+}
+
 int
 sign (Rational r)
 {
   return r.sign ();
 }
+
+bool
+Rational::is_infinity () const
+{
+  return sign_ == 2 || sign_ == -2;
+}