/** {@inheritDoc} */
@Override
public Vector get(Particle particle) {
double averageParticleVelocity = 0.0;
Vector averageVelocity = null; // velocity.getClone();
// averageVelocity.reset();
PSO pso = (PSO) AbstractAlgorithm.get();
for (Particle p : pso.getTopology()) {
if (averageVelocity == null) {
averageVelocity = (Vector) p.getVelocity();
continue;
}
Vector particleVelocity = (Vector) p.getVelocity();
averageVelocity = averageVelocity.plus(particleVelocity);
averageParticleVelocity += particleVelocity.norm();
}
averageVelocity = averageVelocity.divide(particle.getDimension());
averageParticleVelocity /= particle.getDimension();
double swarmCenterVelocity = averageVelocity.norm();
double swarmCoherence = calculateSwarmCoherence(swarmCenterVelocity, averageParticleVelocity);
double sigmoidValue = this.sigmoid.apply(swarmCoherence);
Vector standardVelocity = this.delegate.get(particle);
Vector.Builder builder = Vector.newBuilder();
for (int i = 0; i < particle.getDimension(); ++i) {
double coherenceVelocity =
this.scalingFactor.getParameter()
* sigmoidValue
* averageVelocity.doubleValueOf(i)
* this.randomNumber.getRandomNumber();
builder.add(coherenceVelocity);
}
Vector coherence = builder.build();
return Vectors.sumOf(standardVelocity, coherence);
// float social = socialRandomGenerator.nextFloat();
// float cognitive = cognitiveRandomGenerator.nextFloat();
//
// //DistanceMeasure adm = new AbsoluteDistanceMeasure();
// //DistanceMeasure dm = new MetricDistanceMeasure();
//
// double avgv = 0.0;
// double swv = 0.0;
// Topology<Particle> topology = ((PSO)Algorithm.get()).getTopology();
// Iterator<? extends Particle> it = topology.neighbourhood(null);
// double[] al = new double[particle.getDimension()];
// while (it.hasNext()) {
// Particle pl = it.next();
// double tmpv = 0.0;
// //double tmpsv = 0.0;
// for(int dim = 0; dim < particle.getDimension(); dim++) {
// al[dim] = al[dim]+((Vector)pl.getVelocity()).getReal(dim);
// tmpv += Math.pow(((Vector)pl.getVelocity()).getReal(dim), 2);
// }
// tmpv = Math.sqrt(tmpv);
// avgv += tmpv;
// }
// for(int i = 0; i < particle.getDimension(); i++) {
// //al.set(i, ;
// swv += (al[i]/topology.size()) * (al[i]/topology.size());
// }
// swv = Math.sqrt(swv);
//
// for (int i = 0; i < particle.getDimension(); ++i) {
// double tmp = 0.0;
// tmp = inertiaWeight.getParameter()*velocity.getReal(i)
// + cognitive * (bestPosition.getReal(i) - position.getReal(i)) *
// cognitiveAcceleration.getParameter()
// + social * (nBestPosition.getReal(i) - position.getReal(i)) *
// socialAcceleration.getParameter();
//
// double avgdim = 0.0;
// it = topology.neighbourhood(null);
// while (it.hasNext()) {
// avgdim += ((Vector)(it.next().getVelocity())).getReal(i);
// }
// avgdim /= particle.getDimension();
//
// double cvelocity = MathUtil.sigmoid(swv/avgv)*avgdim*randomNumber.getCauchy();
//
// System.out.println(cvelocity);
// tmp += cvelocity;
//
// velocity.setReal(i, tmp);
//
// clamp(velocity, i);
// }
}
