/** {@inheritDoc} */
@Override
public void absorb(Niche algorithm) {
for (PopulationBasedAlgorithm pba : algorithm.getPopulations()) {
RadiusVisitor radiusVisitor = new RadiusVisitor();
pba.accept(radiusVisitor);
double radius = radiusVisitor.getResult().doubleValue();
Topology<? extends Entity> mainSwarmTopology = algorithm.getMainSwarm().getTopology();
for (int i = 0; i < mainSwarmTopology.size(); i++) {
Entity entity = mainSwarmTopology.get(i);
double distance =
distanceMeasure.distance(
entity.getCandidateSolution(),
Topologies.getBestEntity(pba.getTopology()).getCandidateSolution());
if (distance <= radius) {
Particle p = (Particle) entity;
p.setVelocityProvider(new GCVelocityProvider());
p.setNeighbourhoodBest((Particle) Topologies.getBestEntity(pba.getTopology()));
Topology<Particle> topology = (Topology<Particle>) pba.getTopology();
topology.add(p);
algorithm.getMainSwarm().getTopology().remove(entity);
}
}
}
}
/** Test velocity clamping. */
@Test
public void testClamping() {
Particle particle = createParticle(Vector.of(0.0));
Particle nBest = createParticle(Vector.of(1.0));
particle.setNeighbourhoodBest(nBest);
nBest.setNeighbourhoodBest(nBest);
ClampingVelocityProvider velocityProvider = new ClampingVelocityProvider();
velocityProvider.setVMax(new ConstantControlParameter(0.5));
Vector velocity = velocityProvider.get(particle);
for (Numeric number : velocity) {
Assert.assertTrue(Double.compare(number.doubleValue(), 0.5) <= 0);
Assert.assertTrue(Double.compare(number.doubleValue(), -0.5) >= 0);
}
}