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Added blank lines and fixed run_testing

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SimpleArt
2020-10-12 19:57:57 -04:00
parent 4770473825
commit 3424fd4da7
9 changed files with 86 additions and 18 deletions
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13
src/parent_selection/parent_selection_methods.py
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@ -5,7 +5,9 @@ from initialization.population_structure.population import Population
from initialization.chromosome_structure.chromosome import Chromosome
class Parent_Selection:
class Tournament:
def with_replacement(ga):
"""
Will make tournaments of size tournament_size and choose the winner (best fitness) from the tournament and use it as a parent for the next generation
@ -33,7 +35,9 @@ class Parent_Selection:
if random.uniform(0, 1) < selection_probability * pow(1-selection_probability, index):
ga.population.mating_pool.append(tournament_group[index])
class Roulette:
def roulette_selection(ga):
"""Roulette selection works based off of how strong the fitness is of the
chromosomes in the population. The stronger the fitness the higher the probability
@ -41,22 +45,23 @@ class Parent_Selection:
Where the chromosomes are the numbers to be selected and the board size for
those numbers are directly proportional to the chromosome's current fitness. Where
the ball falls is a randomly generated number between 0 and 1"""
total_fitness = sum(ga.population.chromosome_list[i].get_fitness() for i in range(ga.population.size()))
rel_fitnesses = []
for chromosome in ga.population.chromosome_list:
if (total_fitness != 0):
rel_fitnesses.append(float(chromosome.fitness)/total_fitness)
probability = [sum(rel_fitnesses[:i+1]) for i in range(len(rel_fitnesses))]
while (len(ga.population.mating_pool) < ga.population.size()*ga.parent_ratio):
rand_number = random.random()
# Loop through the list of probabilities
for i in range(len(probability)):
# If the probability is greater than the random_number, then select that chromosome
if (probability[i] >= rand_number):
ga.population.mating_pool.append(ga.population.chromosome_list[i])
# print (f'Selected chromosome : {i}')
break
break