ec.es

Class ESSelection

java.lang.Object

ec.BreedingSource

ec.SelectionMethod

ec.es.ESSelection

All Implemented Interfaces:

Prototype, Setup, RandomChoiceChooserD, Serializable, Cloneable

public class ESSelection
extends SelectionMethod

ESSelection is a special SelectionMethod designed to be used with evolutionary strategies-type breeders.

To do evolution strategies evolution, the breeding pipelines should contain at least one ESSelection selection method. While a child is being generated by the pipeline, the ESSelection object will return a parent from the pool of mu parents. The particular parent is chosen round-robin, so all the parents will have an equal number of children. It's perfectly fine to have more than one ESSelection object in the tree, or to call the same one repeatedly during the course of generating a child; all such objects will consistently return the same parent. They only increment to the nex parent in the pool of mu parents after the child has been created from the pipeline. You can also mix ESSelection operators with other operators (like Tournament Selection). But you ought to have at least one ESSelection operator in the pipeline -- else it wouldn't be Evolution Strategies, would it?

Default Base
es.select

Version:

1.0

Author:

Sean Luke

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static String	P_ESSELECT

Fields inherited from class ec.SelectionMethod

INDS_PRODUCED

Fields inherited from class ec.BreedingSource

NO_PROBABILITY, P_PROB, probability

Constructor Summary

Constructors

Constructor and Description
ESSelection()

Method Summary

Methods

Modifier and Type	Method and Description
Parameter	defaultBase() Returns the default base for this prototype.
void	prepareToProduce(EvolutionState state, int subpopulation, int thread) A default version of prepareToProduce which does nothing.
int	produce(int subpopulation, EvolutionState state, int thread) An alternative form of "produce" special to Selection Methods; selects an individual from the given subpopulation and returns its position in that subpopulation.
int	produce(int min, int max, int start, int subpopulation, Individual[] inds, EvolutionState state, int thread) Produces n individuals from the given subpopulation and puts them into inds[start...start+n-1], where n = Min(Max(q,min),max), where q is the "typical" number of individuals the BreedingSource produces in one shot, and returns n.

Methods inherited from class ec.SelectionMethod

finishProducing, produces, typicalIndsProduced

Methods inherited from class ec.BreedingSource

clone, getProbability, pickRandom, preparePipeline, setProbability, setup, setupProbabilities

Methods inherited from class java.lang.Object

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

Field Detail

P_ESSELECT

public static final String P_ESSELECT

See Also:

Constant Field Values

Constructor Detail

ESSelection

public ESSelection()

Method Detail

defaultBase

public Parameter defaultBase()

Description copied from interface: Prototype

Returns the default base for this prototype. This should generally be implemented by building off of the static base() method on the DefaultsForm object for the prototype's package. This should be callable during setup(...).

prepareToProduce

public void prepareToProduce(EvolutionState state,
                    int subpopulation,
                    int thread)

Description copied from class: SelectionMethod

A default version of prepareToProduce which does nothing.

Overrides:

prepareToProduce in class SelectionMethod

produce

public int produce(int subpopulation,
          EvolutionState state,
          int thread)

Description copied from class: SelectionMethod

An alternative form of "produce" special to Selection Methods; selects an individual from the given subpopulation and returns its position in that subpopulation.

Specified by:

produce in class SelectionMethod

produce

public int produce(int min,
          int max,
          int start,
          int subpopulation,
          Individual[] inds,
          EvolutionState state,
          int thread)

Description copied from class: BreedingSource

Produces n individuals from the given subpopulation and puts them into inds[start...start+n-1], where n = Min(Max(q,min),max), where q is the "typical" number of individuals the BreedingSource produces in one shot, and returns n. max must be >= min, and min must be >= 1. For example, crossover might typically produce two individuals, tournament selection might typically produce a single individual, etc.

Overrides:

produce in class SelectionMethod