org.jgap.impl
Class TournamentSelector

java.lang.Object
  org.jgap.NaturalSelector
      org.jgap.impl.TournamentSelector

All Implemented Interfaces:

java.io.Serializable, Configurable, INaturalSelector

public class TournamentSelector
extends NaturalSelector

Implementation of a NaturalSelector that plays tournaments to determine the chromosomes to be taken to the next generation.

The tournament size can be adjusted as well as the probability for selecting an individual.

Since:

2.0

See Also:

Serialized Form

Constructor Summary

TournamentSelector()
Default constructor.

TournamentSelector(Configuration a_config, int a_tournament_size, double a_probability)

Method Summary

protected void	add(IChromosome a_chromosomeToAdd) Add a Chromosome instance to this selector's working pool of Chromosomes.
void	empty() Empty out the working pool of Chromosomes.
double	getProbability()
int	getTournamentSize()
boolean	returnsUniqueChromosomes()
void	select(int a_howManyToSelect, Population a_from_pop, Population a_to_pop) Select a given number of Chromosomes from the pool that will move on to the next generation population.
void	setProbability(double a_probability)
void	setTournamentSize(int a_tournament_size)

Methods inherited from class org.jgap.NaturalSelector

getConfiguration

Methods inherited from class java.lang.Object

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

Constructor Detail

TournamentSelector

public TournamentSelector()

Default constructor.

Attention: The configuration used is the one set with the static method Genotype.setConfiguration.

TournamentSelector

public TournamentSelector(Configuration a_config,
                          int a_tournament_size,
                          double a_probability)

Parameters:

a_config - the configuration to use

a_tournament_size - the size of each tournament to play

a_probability - probability for selecting the best individuals

Since:

2.0

Method Detail

setTournamentSize

public void setTournamentSize(int a_tournament_size)

getTournamentSize

public int getTournamentSize()

getProbability

public double getProbability()

setProbability

public void setProbability(double a_probability)

select

public void select(int a_howManyToSelect,
                   Population a_from_pop,
                   Population a_to_pop)

Select a given number of Chromosomes from the pool that will move on to the next generation population. This selection will be guided by the fitness values. The chromosomes with the best fitness value win.

Parameters:

a_howManyToSelect - int

a_from_pop - the population the Chromosomes will be selected from

a_to_pop - the population the Chromosomes will be added to

Since:

2.0

returnsUniqueChromosomes

public boolean returnsUniqueChromosomes()

Returns:

false as we allow to return the same chromosome multiple times

Since:

2.0

empty

public void empty()

Description copied from interface: INaturalSelector

Empty out the working pool of Chromosomes. This will be invoked after each evolution cycle so that the natural selector can be reused for the next one.

add

protected void add(IChromosome a_chromosomeToAdd)

Description copied from class: NaturalSelector

Add a Chromosome instance to this selector's working pool of Chromosomes.

Specified by:

add in class NaturalSelector

Parameters:

a_chromosomeToAdd - the Chromosome to add

Since:

2.0