geneticengine.algorithms.gp.operators.selection

Module Contents

Classes

TournamentSelection

TournamentSelection represents a tournament selection algorithm, where

LexicaseSelection

Implements Lexicase Selection
class geneticengine.algorithms.gp.operators.selection.TournamentSelection(tournament_size, with_replacement=False)

Bases: geneticengine.algorithms.gp.structure.GeneticStep

TournamentSelection represents a tournament selection algorithm, where tournament_size individuals are selected at random, and only the best passes to the next generation.

Parameters:

  • tournament_size (int) – number of individuals from the population that will be randomly selected

  • with_replacement (bool) – whether the selected individuals can appear again in another tournament (default: False)

iterate(problem, evaluator, representation, random, population, target_size, generation)
Parameters:
Return type:

list[geneticengine.solutions.individual.Individual]

class geneticengine.algorithms.gp.operators.selection.LexicaseSelection(epsilon=False)

Bases: geneticengine.algorithms.gp.structure.GeneticStep

Implements Lexicase Selection (http://williamlacava.com/research/lexicase/).

Parameters:

epsilon (bool) – if True, espilon-lexicase is performed. We use the method given by equation 5 in https://dl.acm.org/doi/pdf/10.1145/2908812.2908898.

iterate(problem, evaluator, representation, random, population, target_size, generation)
Parameters:
Return type:

list[geneticengine.solutions.individual.Individual]