Class: EvoSynth::Selections::RouletteWheelSelection

Inherits:
FitnessProportionalSelection show all
Defined in:
lib/evosynth/operators/selections/roulette_wheel_selection.rb

Overview

STOCHASTISCHES-UNIVERSELLES-SAMPLING (Weicker Page 75)

Instance Method Summary collapse

Instance Method Details

#select(population, select_count = 1) ⇒ Object

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# File 'lib/evosynth/operators/selections/roulette_wheel_selection.rb', line 33

def select(population, select_count = 1)
	selected_population = EvoSynth::Population.new
	fitness_hash = generate_fitness_hash(population)

	limit = EvoSynth.rand(fitness_hash[population.size - 1] / select_count)

	select_count.to_i.times do
		next_individual = select_next_individual(population, limit, fitness_hash)
		selected_population.add(next_individual)
		limit += fitness_hash[population.size - 1] / select_count
	end

	selected_population
end

#to_s ⇒ Object

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# File 'lib/evosynth/operators/selections/roulette_wheel_selection.rb', line 48

def to_s
	"roulette wheel selection"
end