Changeset 11732 for branches/HeuristicLab.Problems.GrammaticalOptimization/HeuristicLab.Problems.GrammaticalOptimization/SymbolicRegressionPoly10Problem.cs

Timestamp:

01/07/15 09:21:46 (9 years ago)

Author:

gkronber

Message:

#2283: refactoring and bug fixes

File:

• branches/HeuristicLab.Problems.GrammaticalOptimization/HeuristicLab.Problems.GrammaticalOptimization/SymbolicRegressionPoly10Problem.cs (modified) (2 diffs)

branches/HeuristicLab.Problems.GrammaticalOptimization/HeuristicLab.Problems.GrammaticalOptimization/SymbolicRegressionPoly10Problem.cs

@@ -56 +56 @@
     }
 
-    public double GetBestKnownQuality(int maxLen) {
+    public double BestKnownQuality(int maxLen) {
       // for now only an upper bound is returned, ideally we have an R² of 1.0
       // the optimal R² can only be reached for sentences of at least 23 symbols
@@ -67 +67 @@
 
     public double Evaluate(string sentence) {
-      return RSq(y, Enumerable.Range(0, N).Select(i => interpreter.Interpret(sentence, x[i])).ToArray());
+      return HeuristicLab.Common.Extensions.RSq(y, Enumerable.Range(0, N).Select(i => interpreter.Interpret(sentence, x[i])).ToArray());
     }
 
-    private double RSq(IEnumerable<double> xs, IEnumerable<double> ys) {
-      // two pass implementation, but we don't care
-      var meanX = xs.Average();
-      var meanY = ys.Average();
-
-      var s = 0.0;
-      var ssX = 0.0;
-      var ssY = 0.0;
-      foreach (var p in xs.Zip(ys, (x, y) => new { x, y })) {
-        s += (p.x - meanX) * (p.y - meanY);
-        ssX += Math.Pow(p.x - meanX, 2);
-        ssY += Math.Pow(p.y - meanY, 2);
-      }
-
-      if (s.IsAlmost(0)) return 0;
-      if (ssX.IsAlmost(0) || ssY.IsAlmost(0)) return 0;
-      return s * s / (ssX * ssY);
-    }