org.uncommons.watchmaker.framework
Interface SelectionStrategy<T>

Type Parameters:

T - The type of evolved entity that we are selecting.

All Known Implementing Classes:

InteractiveSelection, RankSelection, RouletteWheelSelection, SigmaScaling, StochasticUniversalSampling, TournamentSelection, TruncationSelection

public interface SelectionStrategy<T>

Strategy interface for "natural" selection.

Author:

Daniel Dyer

Method Summary

<S extends T> List<S>

select(List<EvaluatedCandidate<S>> population, boolean naturalFitnessScores, int selectionSize, Random rng) Select the specified number of candidates from the population.

Method Detail

select

<S extends T> List<S> select(List<EvaluatedCandidate<S>> population,
                             boolean naturalFitnessScores,
                             int selectionSize,
                             Random rng)

Select the specified number of candidates from the population. Implementations may assume that the population is sorted in descending order according to fitness (so the fittest individual is the first item in the list).

It is an error to call this method with an empty or null population.

Type Parameters:

S - The type of evolved entity that we are selecting, a sub-type of T.

Parameters:

population - The population from which to select.

naturalFitnessScores - Whether higher fitness values represent fitter individuals or not.

selectionSize - The number of individual selections to make (not necessarily the number of distinct candidates to select, since the same individual may potentially be selected more than once).

rng - Source of randomness for stochastic selection strategies.

Returns:

A list containing the selected candidates. Some individual canidates may potentially have been selected multiple times.