Changeset 16308 for branches/2845_EnhancedProgress/HeuristicLab.Algorithms.DataAnalysis/3.4/TSNE/Distances/CosineDistance.cs

Timestamp:

11/20/18 13:52:40 (6 years ago)

Author:

pfleck

Message:

#2845 reverted the last merge (r16307) because some revisions were missing

Location:

branches/2845_EnhancedProgress

Files:

• . (modified) (1 prop)
• HeuristicLab.Algorithms.DataAnalysis (modified) (1 prop)
• HeuristicLab.Algorithms.DataAnalysis/3.4 (modified) (1 prop)
• HeuristicLab.Algorithms.DataAnalysis/3.4/TSNE/Distances/CosineDistance.cs (modified) (5 diffs)

branches/2845_EnhancedProgress/HeuristicLab.Algorithms.DataAnalysis/3.4/TSNE/Distances/CosineDistance.cs

@@ -1 +1 @@
 #region License Information
 /* HeuristicLab
- * Copyright (C) 2002-2018 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
+ * Copyright (C) 2002-2016 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
  *
  * This file is part of HeuristicLab.
@@ -22 +22 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using HeuristicLab.Common;
 using HeuristicLab.Core;
@@ -27 +28 @@
 
 namespace HeuristicLab.Algorithms.DataAnalysis {
+
   /// <summary>
   /// The angular distance as defined as a normalized distance measure dependent on the angle between two vectors.
@@ -33 +35 @@
   [Item("CosineDistance", "The angular distance as defined as a normalized distance measure dependent on the angle between two vectors.")]
   public class CosineDistance : DistanceBase<IEnumerable<double>> {
+
     #region HLConstructors & Cloning
     [StorableConstructor]
@@ -45 +48 @@
 
     #region statics
-    public static double GetDistance(IEnumerable<double> point1, IEnumerable<double> point2) {
-      using (IEnumerator<double> p1Enum = point1.GetEnumerator(), p2Enum = point2.GetEnumerator()) {
-        var innerprod = 0.0;
-        var length1 = 0.0;
-        var length2 = 0.0;
-        while (p1Enum.MoveNext() & p2Enum.MoveNext()) {
-          double d1 = p1Enum.Current, d2 = p2Enum.Current;
-          innerprod += d1 * d2;
-          length1 += d1 * d1;
-          length2 += d2 * d2;
-        }
-        var divisor = Math.Sqrt(length1 * length2);
-        if (divisor.IsAlmost(0)) throw new ArgumentException("Cosine distance is not defined on vectors of length 0");
-        if (p1Enum.MoveNext() || p2Enum.MoveNext()) throw new ArgumentException("Cosine distance not defined on vectors of different length");
-        return 1 - innerprod / divisor;
+    public static double GetDistance(IReadOnlyList<double> point1, IReadOnlyList<double> point2) {
+      if (point1.Count != point2.Count) throw new ArgumentException("Cosine distance not defined on vectors of different length");
+      var innerprod = 0.0;
+      var length1 = 0.0;
+      var length2 = 0.0;
+
+      for (var i = 0; i < point1.Count; i++) {
+        double d1 = point1[i], d2 = point2[i];
+        innerprod += d1 * d2;
+        length1 += d1 * d1;
+        length2 += d2 * d2;
       }
+      var l = Math.Sqrt(length1 * length2);
+      if (l.IsAlmost(0)) throw new ArgumentException("Cosine distance is not defined on vectors of length 0");
+      return 1 - innerprod / l;
     }
     #endregion
     public override double Get(IEnumerable<double> a, IEnumerable<double> b) {
-      return GetDistance(a, b);
+      return GetDistance(a.ToArray(), b.ToArray());
     }
   }