X-Git-Url: https://git.donarmstrong.com/?a=blobdiff_plain;f=lily%2Fleast-squares.cc;h=492f5ff65d47c9694f22fcc2b967d5f934eb879e;hb=5b4b0d6e9a197e8f9eb085b7c2ad78b8be3e5cfc;hp=bcb2cb1a9b55336df1c6cde2bf96075ca671bbe6;hpb=7e72a1e50e94a7f9738d62599de79fe7745f600c;p=lilypond.git

diff --git a/lily/least-squares.cc b/lily/least-squares.cc
index bcb2cb1a9b..492f5ff65d 100644
--- a/lily/least-squares.cc
+++ b/lily/least-squares.cc
@@ -1,50 +1,52 @@
-/*   
-  least-squares.cc --  implement minimise_least_squares
-  
+/*
+  least-squares.cc -- implement minimise_least_squares
+
   source file of the GNU LilyPond music typesetter
-  
-  (c) 1996--2004 Han-Wen Nienhuys <hanwen@cs.uu.nl>
-  
- */
+
+  (c) 1996--2008 Han-Wen Nienhuys <hanwen@xs4all.nl>
+*/
 
 #include "least-squares.hh"
-#include "warn.hh"
 
+#include "warn.hh"
 
 void
-minimise_least_squares (Real * coef, Real * offset,
-			Array<Offset> const &input)
+minimise_least_squares (Real *coef, Real *offset,
+			vector<Offset> const &input)
 {
   Real sx = 0.0;
   Real sy = 0.0;
-  Real sqx =0.0;
+  Real sqx = 0.0;
   Real sxy = 0.0;
 
-  for (int i=0; i < input.size ();i++) 
+  for (vsize i = 0; i < input.size ();i++)
     {
-      Real x=input[i][X_AXIS];
+      Real x = input[i][X_AXIS];
       Real y = input[i][Y_AXIS];
       sx += x;
       sy += y;
       sqx += sqr (x);
       sxy += x*y;
     }
-  int N = input.size ();
 
-  *coef =0.0;
-  *offset =0.;
-  
-  Real den = (N*sqx - sqr (sx));
-  if (!N || !den)
+  int count = input.size ();
+
+  *coef = 0.0;
+  *offset = 0.;
+
+  Real den = (count * sqx - sqr (sx));
+  if (!count || !den)
     {
-      programming_error ("minimise_least_squares ():  Nothing to minimise");
+      programming_error ("minimise_least_squares ():  Nothing to minimise\n"
+			 "This means that vertical spacing is triggered\n"
+			 "before line breaking\n");
       *coef = 0.0;
-      *offset = N ? sy/N : 0.0;
+      *offset = count ? sy / count : 0.0;
     }
   else
     {
-      *coef = (N * sxy - sx*sy)/den;
-      *offset = (sy - (*coef) * sx)/N;
+      *coef = (count * sxy - sx * sy) / den;
+      *offset = (sy - (*coef) * sx) / count;
     }
 }