Package ec.select

# Class FitProportionateSelection

java.lang.Object
ec.BreedingSource
ec.SelectionMethod
ec.select.FitProportionateSelection

All Implemented Interfaces:
  `Prototype`, `Setup`, `RandomChoiceChooserD`, `Serializable`, `Cloneable`

Direct Known Subclasses:
  `BoltzmannSelection`, `SigmaScalingSelection`

public class FitProportionateSelection extends SelectionMethod
Picks individuals in a population in direct proportion to their fitnesses as returned by their fitness() methods. This is expensive to set up and bring down, so it's not appropriate for steady-state evolution. If you're not familiar with the relative advantages of selection methods and just want a good one, use TournamentSelection instead. Not appropriate for multiobjective fitnesses.

Note: Fitnesses must be non-negative. 0 is assumed to be the worst fitness.

Typical Number of Individuals Produced Per `produce(...)` call
Always 1.

Default Base
select.fitness-proportionate

See Also:
  - Serialized Form

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `double[]`
  `fitnesses`
  Normalized, totalized fitnesses for the population
  `static final String`
  `P_FITNESSPROPORTIONATE`
  Default base

  ### Fields inherited from class ec.SelectionMethod

  `INDS_PRODUCED, KEY_PARENTS`

  ### Fields inherited from class ec.BreedingSource

  `NO_PROBABILITY, P_PROB, probability`

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `FitProportionateSelection()`

- ## Method Summary

  Modifier and Type
  Method
  Description
  `Parameter`
  `defaultBase()`
  Returns the default base for this prototype.
  `void`
  `finishProducing(EvolutionState s, int subpopulation, int thread)`
  A default version of finishProducing, which does nothing.
  `void`
  `prepareToProduce(EvolutionState s, 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.

  ### Methods inherited from class ec.SelectionMethod

  `produce, produces, produceWithoutCloning, typicalIndsProduced`

  ### Methods inherited from class ec.BreedingSource

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

  ### Methods inherited from class java.lang.Object

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

- ## Field Details

  - ### P_FITNESSPROPORTIONATE

    public static final String P_FITNESSPROPORTIONATE
    Default base
    See Also:
      - Constant Field Values

  - ### fitnesses

    public double[] fitnesses
    Normalized, totalized fitnesses for the population

- ## Constructor Details

  - ### FitProportionateSelection

    public FitProportionateSelection()

- ## Method Details

  - ### 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 s, 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`

  - ### finishProducing

    public void finishProducing(EvolutionState s, int subpopulation, int thread)
    Description copied from class: `SelectionMethod`
    A default version of finishProducing, which does nothing.
    Overrides:
      `finishProducing` in class `SelectionMethod`