org.jenetics

Class StochasticUniversalSelector<G extends Gene<?,G>,N extends Number & Comparable<? super N>>

java.lang.Object

org.jenetics.ProbabilitySelector<G,N>

org.jenetics.RouletteWheelSelector<G,N>

org.jenetics.StochasticUniversalSelector<G,N>

All Implemented Interfaces:

Selector<G,N>

public class StochasticUniversalSelector<G extends Gene<?,G>,N extends Number & Comparable<? super N>>
extends RouletteWheelSelector<G,N>

StochasticUniversalSelector is a method for selecting a population according to some given probability in a way that minimize chance fluctuations. It can be viewed as a type of roulette game where now we have P equally spaced points which we spin.

The figure above shows how the stochastic-universal selection works; n is the number of individuals to select.

Since:

1.0

Version:

3.2

Author:

Franz Wilhelmstötter

See Also:

Wikipedia: Stochastic universal sampling

Constructor Summary

Constructors

Constructor and Description
StochasticUniversalSelector()

Method Summary

Modifier and Type	Method and Description
boolean	equals(Object obj)
int	hashCode()
Population<G,N>	select(Population<G,N> population, int count, Optimize opt) This method sorts the population in descending order while calculating the selection probabilities.
String	toString()

Methods inherited from class org.jenetics.RouletteWheelSelector

probabilities

Methods inherited from class org.jenetics.ProbabilitySelector

probabilities

Methods inherited from class java.lang.Object

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

Constructor Detail

StochasticUniversalSelector

public StochasticUniversalSelector()

Method Detail

select

public Population<G,N> select(Population<G,N> population,
                              int count,
                              Optimize opt)

This method sorts the population in descending order while calculating the selection probabilities. (The method Population.populationSort() is called by this method.)

Specified by:

select in interface Selector<G extends Gene<?,G>,N extends Number & Comparable<? super N>>

Overrides:

select in class ProbabilitySelector<G extends Gene<?,G>,N extends Number & Comparable<? super N>>

Parameters:

population - The population to select from.

count - The number of phenotypes to select.

opt - Determines whether the individuals with higher fitness values or lower fitness values must be selected. This parameter determines whether the GA maximizes or minimizes the fitness function.

Returns:

The selected phenotypes (a new Population).

hashCode

public int hashCode()

Overrides:

hashCode in class RouletteWheelSelector<G extends Gene<?,G>,N extends Number & Comparable<? super N>>

equals

public boolean equals(Object obj)

Overrides:

equals in class RouletteWheelSelector<G extends Gene<?,G>,N extends Number & Comparable<? super N>>

toString

public String toString()

Overrides:

toString in class RouletteWheelSelector<G extends Gene<?,G>,N extends Number & Comparable<? super N>>