Changeset 15091 for trunk/sources/HeuristicLab.Encodings.RealVectorEncoding/3.3/ParticleOperators/RealVectorNeighborhoodParticleUpdater.cs

Timestamp:

06/29/17 15:26:16 (7 years ago)

Author:

abeham

Message:

#2797:

• Updated PSO to make it more compatible with SPSO 2011
• Removed truncation of velocity vector and instead rescaled it given the maximum velocity
• Added non-zero initial velocity according to SPSO 2011
• Removed complicated bouncing code due to box constraints and instead implemented as described in SPSO 2011
• Calculating neighbor best has been changed to use personal best
• Avoiding local and global particle update and instead relying on neighborbest
• More randomization during velocity update by using a separate random numbers per dimension
• Reusing problem specific solution creator in RealVectorParticleCreator instead of always using UniformRandomRealVectorCreator

File:

• trunk/sources/HeuristicLab.Encodings.RealVectorEncoding/3.3/ParticleOperators/RealVectorNeighborhoodParticleUpdater.cs (modified) (3 diffs)

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

@@ -22 +22 @@
 using HeuristicLab.Common;
 using HeuristicLab.Core;
-using HeuristicLab.Optimization;
 using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
 
@@ -28 +27 @@
   [Item("Neighborhood Particle Updater", "Updates the particle's position using (among other things) the best neighbor's position. Point = Point + Velocity*Inertia + (PersonalBestPoint-Point)*Phi_P*r_p + (BestNeighborPoint-Point)*Phi_G*r_g.")]
   [StorableClass]
-  public sealed class RealVectorNeighborhoodParticleUpdater : RealVectorParticleUpdater, ILocalParticleUpdater {
+  public sealed class RealVectorNeighborhoodParticleUpdater : RealVectorParticleUpdater {
 
     #region Construction & Cloning
@@ -41 +40 @@
 
     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();
-
-      for (int i = 0; i < velocity.Length; i++) {
-        velocity[i] =
-          Velocity[i] * inertia +
-          (PersonalBest[i] - RealVector[i]) * personalBestAttraction * r_p +
-          (BestPoint[i] - RealVector[i]) * neighborBestAttraction * r_g;
-      }
-
-      MoveParticle(velocity, position);
+      UpdateVelocity();
+      UpdatePosition();
 
       return base.Apply();