/*
* Encog(tm) Core v2.5 - Java Version
* http://www.heatonresearch.com/encog/
* http://code.google.com/p/encog-java/
* Copyright 2008-2010 Heaton Research, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* For more information on Heaton Research copyrights, licenses
* and trademarks visit:
* http://www.heatonresearch.com/copyright
*/
package org.encog.solve.genetic.mutate;
import org.encog.solve.genetic.genes.DoubleGene;
import org.encog.solve.genetic.genes.Gene;
import org.encog.solve.genetic.genome.Chromosome;
/**
* A simple mutation based on random numbers.
*/
public class MutatePerturb implements Mutate {
/**
* The amount to perturb by.
*/
private final double perturbAmount;
/**
* Construct a perturb mutation.
* @param perturbAmount The amount to mutate by(percent).
*/
public MutatePerturb(final double perturbAmount) {
this.perturbAmount = perturbAmount;
}
/**
* Perform a perturb mutation on the specified chromosome.
* @param chromosome The chromosome to mutate.
*/
public void performMutation(final Chromosome chromosome) {
for (final Gene gene : chromosome.getGenes()) {
if (gene instanceof DoubleGene) {
final DoubleGene doubleGene = (DoubleGene) gene;
double value = doubleGene.getValue();
value += (perturbAmount - (Math.random() * perturbAmount * 2));
doubleGene.setValue(value);
}
}
}
}