jenes.stage.operator.common
Class RouletteWheelSelector<T extends Chromosome>

java.lang.Object
  jenes.stage.AbstractStage<T>
      jenes.stage.operator.Operator<T>
          jenes.stage.operator.Selector<T>
              jenes.stage.operator.common.RouletteWheelSelector<T>

Type Parameters:

T - The class of chromosomes to work with.

public class RouletteWheelSelector<T extends Chromosome>
extends Selector<T>

A classic roulette wheel selection operator. If s if the input population size, s individuals will be selected. The best ones have a higher selection probability. A preSelect(Population) method is useful to set up the selection state according to the population state to undergo at the selection process.

Since:

1.0

Version:

1.2

Author:

Luigi Troiano, Pierpaolo Lombardi, Giuseppe Pascale, Thierry Bodhuin

See Also:

Individual, Population

Nested Class Summary

Nested classes/interfaces inherited from class jenes.stage.operator.Selector

Selector.Statistics

Field Summary

Fields inherited from class jenes.stage.operator.Selector

DEFAULT_MAX_ILLEGAL_RATE

Fields inherited from class jenes.stage.operator.Operator

random, statistics

Fields inherited from class jenes.stage.AbstractStage

biggerIsBetter, ga

Constructor Summary

RouletteWheelSelector()

Method Summary

protected void	preSelect(Population<T> pop) Sets up the selection state according a population's state.
protected Individual<T>	select(Population<T> pop) Selects a population according to a politics of selection.

Methods inherited from class jenes.stage.operator.Selector

getMaxIllegalRate, process, setMaxIllegalRate

Methods inherited from class jenes.stage.operator.Operator

getStatistics, updateStatistics

Methods inherited from class jenes.stage.AbstractStage

dispose, init, isBiggerBetter, setBiggerIsBetter, setBiggerIsBetter

Methods inherited from class java.lang.Object

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

Constructor Detail

RouletteWheelSelector

public RouletteWheelSelector()

Method Detail

preSelect

protected void preSelect(Population<T> pop)

Description copied from class: Selector

Sets up the selection state according a population's state. It's invoked at the start of individuals selection of the specified population.

Overrides:

preSelect in class Selector<T extends Chromosome>

Parameters:

pop - the population to process by the stage

select

protected Individual<T> select(Population<T> pop)

Description copied from class: Selector

Selects a population according to a politics of selection.

Specified by:

select in class Selector<T extends Chromosome>

Parameters:

pop - the population in which to choose the individual

Returns:

the position selected