orbital.algorithm.evolutionary
Class SteadyStateGeneticAlgorithm

java.lang.Object
  orbital.algorithm.evolutionary.GeneticAlgorithm
      orbital.algorithm.evolutionary.SteadyStateGeneticAlgorithm

All Implemented Interfaces:

java.io.Serializable, AlgorithmicTemplate, ProbabilisticAlgorithm

public class SteadyStateGeneticAlgorithm
extends GeneticAlgorithm

A steady state genetic algorithm with overlapping populations. Reproduces a given percentage of the population and replaces (if better).

Note: to make sure this algorithm is compatible with ParallelEvaluationPopulation each new genome that arises is evaluated prior to updating the populaiton.

Author:

André Platzer

See Also:

Serialized Form

Structure:

delegate population:Population, delegate selection:Function

Nested Class Summary

Nested classes/interfaces inherited from class orbital.algorithm.evolutionary.GeneticAlgorithm

GeneticAlgorithm.Configuration

Constructor Summary

protected	SteadyStateGeneticAlgorithm()
	SteadyStateGeneticAlgorithm(int replacements) Construct a new GeneticAlgorithm.

Method Summary

void	evolve() evolves to the next generation for this population.
int	getNumberOfReplacements() Get the number of replacements to do at each generation (=< population.size()).
double	getPopulationGrowth() Get the population growth factor.
void	setNumberOfReplacements(int replacements)

Methods inherited from class orbital.algorithm.evolutionary.GeneticAlgorithm

clone, complexity, equals, getEvaluation, getPopulation, getRandom, getSelection, hashCode, isCorrect, setEvaluation, setPopulation, setRandom, setSelection, solve, spaceComplexity, toString

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

SteadyStateGeneticAlgorithm

public SteadyStateGeneticAlgorithm(int replacements)

Construct a new GeneticAlgorithm.

Parameters:

replacements - the number of replacements to do at each generation (=< population.size()). We will perform as many reproductions such that at least replacement replacements have occured.

SteadyStateGeneticAlgorithm

protected SteadyStateGeneticAlgorithm()

Method Detail

getNumberOfReplacements

public int getNumberOfReplacements()

Get the number of replacements to do at each generation (=< population.size()). We will perform as many reproductions such that at least replacement replacements have occured.

setNumberOfReplacements

public void setNumberOfReplacements(int replacements)

getPopulationGrowth

public double getPopulationGrowth()

Description copied from class: GeneticAlgorithm

Get the population growth factor.

Specified by:

getPopulationGrowth in class GeneticAlgorithm

Returns:

the factor by which the population size increases with each generation (or decreases if < 1).

evolve

public void evolve()

Description copied from class: GeneticAlgorithm

evolves to the next generation for this population. Parents are selected and will recombine and mutate to produce children genomes who will replace some genomes in this population. This operation is sometimes called breeding.

Specified by:

evolve in class GeneticAlgorithm

See Also:

GeneticAlgorithm.selection, Genome.recombine(Gene[],int,double), PopulationImpl.getMaximumRecombination(), PopulationImpl.getMaximumMutation()