Class: Wallace::Selector

Inherits:

Object

• Object
• Wallace::Selector

Defined in:

lib/core/selector.rb

Overview

Selectors are used to select individuals from a set of candidates (usually, but not exclusively the sub-population) as participants in the breeding process.

Different selector classes are used to implement different types of selection rules.

A “prepare” method is provided to allow the list of candidates to be pre-processed, saving time for selection methods such as roulette selection.

Direct Known Subclasses

Wallace::Selectors::RandomSelector, Wallace::Selectors::RouletteSelector, Wallace::Selectors::TournamentSelector

Class Attribute Summary

• .name ⇒ Object

  Returns the value of attribute name.

Instance Method Summary

• #prepare(candidates, opts = {}) ⇒ Object

  Prepares a list of candidates for use with this selector.

• #produce(rng, candidates) ⇒ Object

  Selects a single individual from the list of prepared candidates according to the rules of this selection method.

Class Attribute Details

.name ⇒ Object

Returns the value of attribute name.

# File 'lib/core/selector.rb', line 11

def name
  @name
end

Instance Method Details

#prepare(candidates, opts = {}) ⇒ Object

Prepares a list of candidates for use with this selector. Pre-processing can be performed on this list to improve performance. The list of candidates is not stored by the selector, instead it is stored by an associated input node.

Parameters:

• candidates, the list of candidates to select from.

• opts, a hash of keyword options for this method. -> random, random number generator to use in pre-processing of candidates.

Returns: A prepared list of candidates for use with this selector.

# File 'lib/core/selector.rb', line 26

def prepare(candidates, opts = {})
  candidates
end

#produce(rng, candidates) ⇒ Object

Selects a single individual from the list of prepared candidates according to the rules of this selection method.

Parameters:

• rng, the RNG to use to inform the choice of candidate.

• candidates, the candidate individuals for selection.

Returns: A selected individual from the list of candidates.

Raises:

• (NotImplementedError)

# File 'lib/core/selector.rb', line 39

def produce(rng, candidates)
  raise NotImplementedError, 'No produce function was implemented by this selector.'
end