/** {@inheritDoc} */
@Override
public Vector get(Particle particle) {
Vector localGuide = (Vector) particle.getLocalGuide();
Vector globalGuide = (Vector) particle.getGlobalGuide();
PSO pso = (PSO) AbstractAlgorithm.get();
List<Entity> positions = getRandomParentEntities(pso.getTopology());
// select three random individuals, all different and different from particle
ProbabilityDistributionFuction pdf = new UniformDistribution();
Vector position1 = (Vector) positions.get(0).getCandidateSolution();
Vector position2 = (Vector) positions.get(1).getCandidateSolution();
// Vector position3 = (Vector) positions.get(2).getContents();
Vector.Builder builder = Vector.newBuilder();
for (int i = 0; i < particle.getDimension(); ++i) {
double r = pdf.getRandomNumber(0, 1);
double attractor = r * localGuide.doubleValueOf(i) + (1 - r) * globalGuide.doubleValueOf(i);
double stepSize =
this.rand3.getRandomNumber(0, 1)
* (position1.doubleValueOf(i) - position2.doubleValueOf(i));
if (this.rand2.getRandomNumber(0, 1) > this.crossoverProbability.getParameter()) {
builder.add(attractor + stepSize);
} else {
builder.add(((Vector) particle.getPosition()).doubleValueOf(i)); // position3.getReal(i));
}
}
return builder.build();
}
@Override
public Vector get(Particle particle) {
Vector localGuide = (Vector) particle.getLocalGuide();
Vector globalGuide = (Vector) particle.getGlobalGuide();
Vector.Builder builder = Vector.newBuilder();
for (int i = 0; i < particle.getDimension(); ++i) {
if (this.uniform.getRandomNumber(0, 1) < 0.5) {
builder.add(localGuide.doubleValueOf(i));
} else {
// double tmp1 = cognitive.getParameter();
// double tmp2 = social.getParameter();
double sigma = Math.abs(localGuide.doubleValueOf(i) - globalGuide.doubleValueOf(i));
// according to Kennedy
double mean = (localGuide.doubleValueOf(i) + globalGuide.doubleValueOf(i)) / 2;
// andries proposal: double mean = (tmp1*personalBestPosition.getReal(i) +
// tmp2*nBestPosition.getReal(i)) / (tmp1+tmp2);
builder.add(this.randomDistribution.getRandomNumber(mean, sigma));
}
}
return builder.build();
}
