/* * 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); } } } }