[chronojump] Fixing LeastSquares method (unused yet)

[Xavier de Blas <xaviblas src gnome org>]

commit 80cd7259ba1ad2ad338ab2756d61fefbfc09f964
Author: Xavier de Blas <xaviblas gmail com>
Date:   Fri Sep 16 12:02:16 2016 +0200

    Fixing LeastSquares method (unused yet)

 src/Makefile.am       |    1 +
 src/gui/chronojump.cs |    2 +
 src/utilMath.cs       |   87 ++++++++++++++++++++++++++++++++-----------------
 3 files changed, 60 insertions(+), 30 deletions(-)
---
diff --git a/src/Makefile.am b/src/Makefile.am
index 2596c54..00d159e 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -162,6 +162,7 @@ SOURCES = \
        utilEncoder.cs\
        utilGtk.cs\
        utilLanguage.cs\
+       utilMath.cs\
        utilVideo.cs\
        constants.cs\
        report.cs\
diff --git a/src/gui/chronojump.cs b/src/gui/chronojump.cs
index b3a0e4c..bc02214 100644
--- a/src/gui/chronojump.cs
+++ b/src/gui/chronojump.cs
@@ -666,6 +666,8 @@ public partial class ChronoJumpWindow
                label_version.Text = progVersion + buildDate;
                LogB.Information("Build date:" + buildDate);
 
+               LeastSquares ls = new LeastSquares();
+               LogB.Information(string.Format("coef = {0} {1} {2}", ls.Coef[0], ls.Coef[1], ls.Coef[2]));
 
                /*
                 * start a ping in other thread
diff --git a/src/utilMath.cs b/src/utilMath.cs
index 846e2d8..8bf4bb9 100644
--- a/src/utilMath.cs
+++ b/src/utilMath.cs
@@ -19,6 +19,28 @@
  *  Copyright (C) 2016   Xavier de Blas <xaviblas gmail com> 
  */
 
+using System.Collections.Generic; //List<T>
+
+public class Point
+{
+       double x;
+       double y;
+
+       public Point(double x, double y) 
+       {
+               this.x = x;
+               this.y = y;
+       }
+
+       public double X {
+               get { return x; }
+       }
+       
+       public double Y {
+               get { return y; }
+       }
+}
+
 public class LeastSquares 
 {
        //WIP
@@ -31,51 +53,56 @@ public class LeastSquares
                calculate();
        }
 
-       private double [] calculate() 
+       private void calculate() 
        {
-               int numElements = 3;
-               double [numElements,2] measures = { //TODO: pass this values
-                       { 20,30,40 },
-                       { 5,7,9 } };
-
-               double [3] B = new double[3];
-               for(int i = 0; i++; i < 3){
-                       B[0] = B[0] + measures[i][1];
-                       B[1] = B[0] + measures[i][0]*measures[i][1];
-                       B[2] = B[0] + measures[i][0]*measures[i][0]*measures[i][1];
+               //TODO: pass this values
+               List<Point> measures = new List<Point> { 
+                       new Point(1, 10.3214), new Point(2, 13.3214), new Point(3, 18.3214),
+                           new Point(4, 25.3214), new Point(5, 34.3214), new Point(6, 45.3214), 
+                           new Point(7, 58.3214), new Point(8, 73.3214), new Point(9, 90.3214), new 
Point(10, 109.3214) };
+
+               int numMeasures = measures.Count;
+
+               double [] B = new double[3];
+               for(int i = 0; i < numMeasures; i++){
+                       B[0] = B[0] + measures[i].Y;
+                       B[1] = B[0] + measures[i].X * measures[i].Y;
+                       B[2] = B[0] + measures[i].X * measures[i].X * measures[i].Y;
                }
 
+               LogB.Information(string.Format("B = {0} {1} {2}", B[0], B[1], B[2]));
+
                double sumX = 0; //sumatory of the X values
                double sumX2 = 0; //sumatory of the squared X values
                double sumX3 = 0; //sumatory of the cubic X values
 
-               for(int i = 0; i++; i < numElements){
-                       sumX = sumX + measures[i][0];
-                       sumX2 = sumX2 + measures[i][0]*measures[i][0];
-                       sumX3 = sumX3 + measures[i][0]*measures[i][0]*measures[i][0];
+               for(int i = 0; i < numMeasures; i++){
+                       sumX = sumX + measures[i].X;
+                       sumX2 = sumX2 + measures[i].X * measures[i].X;
+                       sumX3 = sumX3 + measures[i].X * measures[i].X * measures[i].X;
                }
 
-               double detA = numElements*sumX2*sumX3 + 2*sumX*sumX2*sumX3 - sumX2*sumX2*sumX2 - 
sumX2*sumX2*sumX3 - numElements*sumX3*sumX3;
+               double detA = numMeasures*sumX2*sumX3 + 2*sumX*sumX2*sumX3 - sumX2*sumX2*sumX2 - 
sumX2*sumX2*sumX3 - numMeasures*sumX3*sumX3;
                if(detA != 0){
-                       double [3][3] invA = new double[3][3];
+                       double [,] invA = new double[3,3];
 
-                       invA[0][0] = ( sumX2*sumX3 - sumX3*sumX3) / detA;
-                       invA[0][1] = (-sumX*sumX3  + sumX2*sumX3) / detA;
-                       invA[0][2] = ( sumX*sumX3  - sumX2*sumX2) / detA;
-                       invA[1][1] = ( numElements*sumX3 - sumX2*sumX2) / detA;
-                       invA[1][2] = (-numElements*sumX3 + sumX*sumX2 ) / detA;
-                       invA[2][2] = ( numElements*sumX2 - sumX*sumX  ) / detA;
+                       invA[0,0] = ( sumX2*sumX3 - sumX3*sumX3) / detA;
+                       invA[0,1] = (-sumX*sumX3  + sumX2*sumX3) / detA;
+                       invA[0,2] = ( sumX*sumX3  - sumX2*sumX2) / detA;
+                       invA[1,1] = ( numMeasures*sumX3 - sumX2*sumX2) / detA;
+                       invA[1,2] = (-numMeasures*sumX3 + sumX*sumX2 ) / detA;
+                       invA[2,2] = ( numMeasures*sumX2 - sumX*sumX  ) / detA;
 
                        //Simetric matrix
-                       invA[1][0] = invA[0][1];
-                       invA[2][0] = invA[0][2];
-                       invA[2][1] = invA[1][2];
+                       invA[1,0] = invA[0,1];
+                       invA[2,0] = invA[0,2];
+                       invA[2,1] = invA[1,2];
 
                        //coef = invA * B
-                       double [3] coef = new double[3];
-                       coef[0] = invA[0][0]*B[0] + invA[0][1]*B[1] + invA[0][2]*B[2];
-                       coef[1] = invA[1][0]*B[0] + invA[1][1]*B[1] + invA[1][2]*B[2];
-                       coef[2] = invA[2][0]*B[0] + invA[2][1]*B[1] + invA[2][2]*B[2];
+                       double [] coef = new double[3];
+                       coef[0] = invA[0,0]*B[0] + invA[0,1]*B[1] + invA[0,2]*B[2];
+                       coef[1] = invA[1,0]*B[0] + invA[1,1]*B[1] + invA[1,2]*B[2];
+                       coef[2] = invA[2,0]*B[0] + invA[2,1]*B[1] + invA[2,2]*B[2];
 
                        Success = true;
                        Coef = coef;