/*
* SBXCrossoverAndPolynomialMutation.java
*
* @author Antonio J. Nebro
* @version 1.0
*
* This class returns a solution after applying SBX and Polynomial mutation
*/
package jmetal.util.offspring;
import jmetal.core.Operator;
import jmetal.core.Solution;
import jmetal.core.SolutionSet;
import jmetal.operators.mutation.MutationFactory;
import jmetal.operators.selection.SelectionFactory;
import jmetal.util.JMException;
import java.util.HashMap;
import java.util.logging.Level;
import java.util.logging.Logger;
public class DifferentialEvolutionOffspringPolynomial extends Offspring {
private double mutationProbability_ = 0.0;
double crossoverProbability_ = 0.9;
private double distributionIndexForMutation_ = 20;
double distributionIndexForCrossover_ = 20;
private Operator mutation_;
private Operator selection_;
private DifferentialEvolutionOffspringPolynomial(double mutationProbability,
double distributionIndexForMutation
) throws JMException {
HashMap parameters ;
mutationProbability_ = mutationProbability;
distributionIndexForMutation_ = distributionIndexForMutation;
parameters = new HashMap() ;
parameters.put("probability", mutationProbability_) ;
parameters.put("distributionIndex", distributionIndexForMutation_) ;
mutation_ = MutationFactory.getMutationOperator("PolynomialMutation", parameters);
selection_ = SelectionFactory.getSelectionOperator("BinaryTournament", null);
id_ = "Polynomial";
}
public Solution getOffspring(SolutionSet solutionSet) {
Solution[] parents = new Solution[2];
Solution offSpring = null;
try {
offSpring = new Solution((Solution) selection_.execute(solutionSet));
mutation_.execute(offSpring);
//Create a new solution, using DE
} catch (JMException ex) {
Logger.getLogger(DifferentialEvolutionOffspringPolynomial.class.getName()).log(Level.SEVERE, null, ex);
}
return offSpring;
} // getOffspring
public Solution getOffspring(SolutionSet solutionSet, SolutionSet archive) {
Solution[] parents = null;
Solution offSpring = null;
try {
parents[0] = (Solution) selection_.execute(solutionSet);
if (archive.size() > 0) {
parents[1] = (Solution)selection_.execute(archive);
} else {
parents[1] = (Solution)selection_.execute(solutionSet);
}
offSpring = new Solution( new Solution((Solution) selection_.execute(solutionSet)));
mutation_.execute(offSpring);
//Create a new solution, using DE
} catch (JMException ex) {
Logger.getLogger(DifferentialEvolutionOffspringPolynomial.class.getName()).log(Level.SEVERE, null, ex);
}
return offSpring;
} // getOffpring
public Solution getOffspring(Solution solution) {
Solution res = new Solution(solution);
try {
mutation_.execute(res);
} catch (JMException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return res;
}
} // DifferentialEvolutionOffspring