Package org.uma.jmetal.operator.crossover.impl

Class ParentCentricCrossover

java.lang.Object

org.uma.jmetal.operator.crossover.impl.ParentCentricCrossover

All Implemented Interfaces:

Serializable, CrossoverOperator<DoubleSolution>, Operator<List<DoubleSolution>,List<DoubleSolution>>

public class ParentCentricCrossover
extends Object
implements CrossoverOperator<DoubleSolution>

This class implements the Parent-Centric Recombination (PCX) operator for real-valued solutions. PCX is a multi-parent crossover operator that generates offspring based on a normal distribution centered around a parent solution, with spread controlled by the distribution of other parents.

Reference: Deb, K., Anand, A., invalid input: '&' Joshi, D. (2002). A computationally efficient evolutionary algorithm for real-parameter optimization. Evolutionary computation, 10(4), 371-395.

Author:

Antonio J. Nebro

See Also:

• Serialized Form

Constructor Summary

Constructors

Constructor	Description
ParentCentricCrossover(double crossoverProbability)	Constructor with default parameter values
ParentCentricCrossover(double crossoverProbability, double zeta, double eta, RepairDoubleSolution solutionRepair)	Constructor with all parameters
ParentCentricCrossover(double crossoverProbability, double zeta, double eta, RepairDoubleSolution solutionRepair, RandomGenerator<Double> randomGenerator)	Constructor with all parameters including random generator (for testing)

Method Summary

Modifier and Type	Method	Description
double	crossoverProbability()
double	eta()
List<DoubleSolution>	execute(List<DoubleSolution> solutions)
int	numberOfGeneratedChildren()
int	numberOfRequiredParents()
double	zeta()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

ParentCentricCrossover

public ParentCentricCrossover(double crossoverProbability)

Constructor with default parameter values

Parameters:

crossoverProbability - Crossover probability (must be in [0,1])

ParentCentricCrossover

public ParentCentricCrossover(double crossoverProbability,
 double zeta,
 double eta,
 RepairDoubleSolution solutionRepair)

Constructor with all parameters

Parameters:

crossoverProbability - Crossover probability (must be in [0,1])

zeta - Controls the spread along the line connecting parents (typically in [0.1, 0.5])

eta - Controls the spread in orthogonal directions (typically in [0.1, 0.5])

solutionRepair - Strategy for repairing solutions

ParentCentricCrossover

public ParentCentricCrossover(double crossoverProbability,
 double zeta,
 double eta,
 RepairDoubleSolution solutionRepair,
 RandomGenerator<Double> randomGenerator)

Constructor with all parameters including random generator (for testing)

Parameters:

crossoverProbability - Crossover probability (must be in [0,1])

zeta - Controls the spread along the line connecting parents

eta - Controls the spread in orthogonal directions

solutionRepair - Strategy for repairing solutions

randomGenerator - Random number generator

Method Details

execute

public List<DoubleSolution> execute(List<DoubleSolution> solutions)

Specified by:

execute in interface Operator<List<DoubleSolution>,List<DoubleSolution>>

Parameters:

solutions - The data to process

crossoverProbability

public double crossoverProbability()

Specified by:

crossoverProbability in interface CrossoverOperator<DoubleSolution>

numberOfRequiredParents

public int numberOfRequiredParents()

Specified by:

numberOfRequiredParents in interface CrossoverOperator<DoubleSolution>

numberOfGeneratedChildren

public int numberOfGeneratedChildren()

Specified by:

numberOfGeneratedChildren in interface CrossoverOperator<DoubleSolution>

zeta

public double zeta()

Returns:

The zeta parameter (spread along the line connecting parents)

eta

public double eta()

Returns:

The eta parameter (spread in orthogonal directions)