Changeset 5592 for trunk/sources/HeuristicLab.Encodings.RealVectorEncoding/3.3/ParticleOperators/RealVectorNeighborhoodParticleUpdater.cs

Timestamp:

03/02/11 15:22:54 (13 years ago)

Author:

epitzer

Message:

Additional improvements to PSO (#852)

• simplify and clean up RealVectorSwarmUpdater
• make the RealVectorParticleCreator an AlgorithmOperator
• standardize naming of local variables in ParticleUpdaters
• remove default parameter values from main loop
• new implementation of MultiPSOTopologyUpdater (using shuffling)

File:

• trunk/sources/HeuristicLab.Encodings.RealVectorEncoding/3.3/ParticleOperators/RealVectorNeighborhoodParticleUpdater.cs (modified) (2 diffs)

trunk/sources/HeuristicLab.Encodings.RealVectorEncoding/3.3/ParticleOperators/RealVectorNeighborhoodParticleUpdater.cs

@@ -30 +30 @@
   public sealed class RealVectorNeighborhoodParticleUpdater : RealVectorParticleUpdater, ILocalParticleUpdater {
 
+    #region Construction & Cloning
     [StorableConstructor]
     private RealVectorNeighborhoodParticleUpdater(bool deserializing) : base(deserializing) { }
     private RealVectorNeighborhoodParticleUpdater(RealVectorNeighborhoodParticleUpdater original, Cloner cloner) : base(original, cloner) { }
     public RealVectorNeighborhoodParticleUpdater() : base() { }
-
     public override IDeepCloneable Clone(Cloner cloner) {
       return new RealVectorNeighborhoodParticleUpdater(this, cloner);
     }
+    #endregion
 
     public override IOperation Apply() {
+      double inertia = Inertia.Value;
+      double personalBestAttraction = PersonalBestAttraction.Value;
+      double neighborBestAttraction = NeighborBestAttraction.Value;
+
       RealVector velocity = new RealVector(Velocity.Length);
       RealVector position = new RealVector(RealVector.Length);
       double r_p = Random.NextDouble();
       double r_g = Random.NextDouble();
-      double omega = Inertia.Value;
-      double phi_p = PersonalBestAttraction.Value;
-      double phi_g = NeighborBestAttraction.Value;
+
       for (int i = 0; i < velocity.Length; i++) {
         velocity[i] =
-          Velocity[i] * omega +
-          (PersonalBest[i] - RealVector[i]) * phi_p * r_p +
-          (BestPoint[i] - RealVector[i]) * phi_g * r_g;
+          Velocity[i] * inertia +
+          (PersonalBest[i] - RealVector[i]) * personalBestAttraction * r_p +
+          (BestPoint[i] - RealVector[i]) * neighborBestAttraction * r_g;
       }
+
       BoundsChecker.Apply(velocity, VelocityBounds);
       for (int i = 0; i < velocity.Length; i++) {
@@ -58 +62 @@
       }
       BoundsChecker.Apply(position, Bounds);
+
       RealVector = position;
       Velocity = velocity;