public void seek(PositionProvider index) throws IOException {
input.seek(index);
int consumed = (int) index.getNext();
if (consumed != 0) {
// a loop is required for cases where we break the run into two parts
while (consumed > 0) {
readValues(false);
used = consumed;
consumed -= numLiterals;
}
} else {
used = 0;
numLiterals = 0;
}
}
@Override
public Vector get(Particle particle) {
Vector newPos = (Vector) delegate.get(particle);
Particle tmp = particle.getClone();
tmp.setPosition(newPos);
Fitness newFitness = particle.getBehaviour().getFitnessCalculator().getFitness(tmp);
final UniformDistribution uniform = new UniformDistribution();
Vector newPBest =
newPos.plus(
Vector.newBuilder()
.repeat(newPos.size(), Real.valueOf(1.0))
.build()
.multiply(
new P1<Number>() {
@Override
public Number _1() {
return uniform.getRandomNumber(
-granularity.getParameter(), granularity.getParameter());
}
}));
tmp.setPosition(newPos);
Fitness newPBestFitness = particle.getBehaviour().getFitnessCalculator().getFitness(tmp);
if (newPBestFitness.compareTo(newFitness) < 0) {
Vector tmpVector = Vector.copyOf(newPos);
newPos = newPBest;
newPBest = tmpVector;
newPBestFitness = newFitness;
}
double dot =
((Vector) particle.getNeighbourhoodBest().getBestPosition())
.subtract(newPos)
.dot(newPBest.subtract(newPos));
if (dot < 0) {
return (Vector) particle.getPosition();
}
particle.put(Property.BEST_POSITION, newPBest);
particle.put(Property.BEST_FITNESS, newPBestFitness);
return newPos;
}
