Changed implementation framework

Instead of a nested approach, selection/crossover/mutation are all called separately and directly by the GA. selection_impl was also separated into parent_selection_impl and survivor_selection_impl, as both are needed separately.
This commit is contained in:
RyleyGG
2020-10-04 17:59:59 -04:00
parent c18a531034
commit e05aa7f62b
5 changed files with 102 additions and 120 deletions

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@ -16,17 +16,17 @@ class GA:
"""Initialize the GA."""
# Initilization variables
self.chromosome_length = 10
self.population_size = 100
self.population_size = 150
self.chromosome_impl = None
self.gene_impl = None
self.population = None
# Termination varibles
self.current_generation = 0
self.current_fitness = 0
self.generation_goal = 50
self.generation_goal = 100
self.fitness_goal = 3
# Mutation variables
self.mutation_rate = 0.05
self.mutation_rate = 0.10
# Rerun already computed fitness
self.update_fitness = True
@ -34,8 +34,9 @@ class GA:
# Defualt EastGA implimentation structure
self.initialization_impl = Initialization_Types().random_initialization
self.fitness_function_impl = Fitness_Examples().is_it_5
self.mutation_impl = Mutation_Types().random_mutation
self.selection_impl = Selection_Types().Tournament().with_replacement
self.mutation_impl = Mutation_Types().per_gene_mutation
self.parent_selection_impl = Selection_Types().Parent_Selection().Tournament().with_replacement
self.survivor_selection_impl = Selection_Types().Survivor_Selection().repeated_crossover
self.crossover_impl = Crossover_Types().single_point_crossover
self.termination_impl = Termination_Types().generation_based
@ -70,7 +71,11 @@ class GA:
self.initialize_population()
self.set_all_fitness(self.population.chromosomes)
next_population = self.selection_impl(self)
self.parent_selection_impl(self)
next_population = self.crossover_impl(self)
next_population = self.survivor_selection_impl(self, next_population)
next_population.set_all_chromosomes(self.mutation_impl(self, next_population.get_all_chromosomes()))
self.population = next_population
self.set_all_fitness(self.population.chromosomes)

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@ -30,8 +30,10 @@ class Population:
def set_all_chromosomes(self, chromosomes):
self.chromosomes = chromosomes
def set_chromosome(self, chromosomes, index):
self.chromosome[index] = chromosome
def set_chromosome(self, chromosome, index = -1):
if index == -1:
index = len(self.chromosomes)-1
self.chromosomes[index] = chromosome
def set_fitness(self, fitness):
self.fitness = fitness

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@ -8,7 +8,7 @@ class Mutation_Types:
def random_mutation(self, ga, chromosome_set = None):
if chromosome_set == None:
chromosome_set = ga.population
chromosome_set = ga.population.get_all_chromosomes()
chromosome_mutate_num = int(len(chromosome_set)*ga.mutation_rate)
temp_population = ga.initialization_impl(ga)
@ -19,3 +19,24 @@ class Mutation_Types:
return chromosome_set
def per_gene_mutation(self, ga, chromosome_set = None, gene_mutate_count = 1):
gene_mutate_count_static = int(gene_mutate_count)
if chromosome_set == None:
chromosome_set = ga.population.get_all_chromosomes()
for i in range(len(chromosome_set)):
random_num = random.uniform(0,1)
if (random_num <= ga.mutation_rate):
while gene_mutate_count > 0:
dummy_population = ga.initialization_impl(ga) #Really inefficient, but works for now
random_index = random.randint(0, ga.chromosome_length-1)
chromosome_set[i].get_genes()[random_index] = dummy_population.get_all_chromosomes()[random.randint(0,ga.population_size-1)].get_genes()[random_index]
gene_mutate_count -= 1
gene_mutate_count = int(gene_mutate_count_static)
return chromosome_set

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@ -5,7 +5,10 @@ import random
# Create the Genetic algorithm
ga = EasyGA.GA()
ga.gene_impl = [random.randrange,1,25]
#def random_parent_selection(population):
#while ()
ga.gene_impl = [random.randrange,1,100]
# Run Everything
ga.evolve()

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@ -9,11 +9,13 @@ class Selection_Types:
def __init__(self):
pass
class Parent_Selection:
class Tournament:
def with_replacement(self, ga):
tournament_size = int(len(ga.population.get_all_chromosomes())/10) #currently hard-coded for purposes of the example.
if tournament_size < 3:
tournament_size = int(len(ga.population.get_all_chromosomes())/3)
parent_ratio = 0.25
#selection_probability is the likelihood that a chromosome will be selected.
#best chromosome in a tournament is given a selection probablity of selection_probability
@ -22,56 +24,13 @@ class Selection_Types:
selection_probability = 0.95
total_selected = 0 #Total Chromosomes selected
while (total_selected <= ga.population_size*2):
while (total_selected < parent_ratio*ga.population_size):
#create & gather tournament group
tournament_group = []
for i in range(tournament_size):
tournament_group.append(random.choice(ga.population.get_all_chromosomes()))
total_selected = self.selection(tournament_group, tournament_size, total_selected, selection_probability)[0]
new_population = self.create_new_population(ga)
return new_population
def without_replacement(self, ga):
tournament_size = int(len(ga.population.get_all_chromosomes())/10) #currently hard-coded for purposes of the example.
if tournament_size < 3:
tournament_size = int(len(ga.population.get_all_chromosomes())/3)
#selection_probability is the likelihood that a chromosome will be selected.
#best chromosome in a tournament is given a selection probablity of selection_probability
#2nd best is given probability of selection_probability*(1-selection_probability)
#3rd best is given probability of selection_probability*(1-selection_probability)**2
selection_probability = 0.95
total_selected = 0 #Total Chromosomes selected
available_chromosome_indices = []
for i in range(len(ga.population.get_all_chromosomes())):
available_chromosome_indices.append(i)
continue_selecting = True
while (continue_selecting):
#create & gather tournament group
tournament_group = []
for i in range(tournament_size):
selected_chromosome_index = random.choice(available_chromosome_indices)
tournament_group.append(ga.population.get_all_chromosomes()[selected_chromosome_index])
winning_chromosome_index = self.selection(tournament_group, tournament_size, total_selected, selection_probability)[1]
for i in range(len(available_chromosome_indices)):
if tournament_group[winning_chromosome_index].selected:
del available_chromosome_indices[i]
break
#print(winning_chromosome_index)
#print(available_chromosome_indices)
if len(available_chromosome_indices) < 1:
continue_selecting = False
new_population = self.create_new_population(ga)
return new_population
def selection(self, tournament_group, tournament_size, total_selected, selection_probability):
#Sort the tournament contenders based on their fitness
#currently hard-coded to only consider higher fitness = better; can be changed once this impl is agreed on
#also currently uses bubble sort because its easy
@ -108,14 +67,9 @@ class Selection_Types:
selected_chromosome_tournament_index = i
break
return total_selected,selected_chromosome_tournament_index
def create_new_population(self, ga):
new_population = ga.crossover_impl(ga)
#If the crossover doesn't create enough chromosomes (ugly right now pls no judgerino, can be changed)
#Just does single-point crossover at random indices
while len(new_population.chromosomes) < ga.population_size:
class Survivor_Selection:
def repeated_crossover(self, ga, next_population):
while len(next_population.chromosomes) < ga.population_size:
crossover_pool = []
for i in range(ga.population_size):
if ga.population.get_all_chromosomes()[i].selected:
@ -130,18 +84,15 @@ class Selection_Types:
parent_two = crossover_pool[i+1].get_genes()
new_gene_set.extend(parent_one[0:split_point])
new_gene_set.extend(parent_two[split_point:])
new_chromosome = Chromosome(new_gene_set)
new_chromosome = create_chromosome(new_gene_set)
chromosome_list.append(new_chromosome)
for i in range(len(chromosome_list)):
new_population.add_chromosome(chromosome_list[i])
if len(new_population.chromosomes) >= ga.population_size:
next_population.add_chromosome(chromosome_list[i])
if len(next_population.chromosomes) >= ga.population_size:
break
new_chromosome_set = ga.mutation_impl(ga, new_population.get_all_chromosomes())
new_population.set_all_chromosomes(new_chromosome_set)
return new_population
return next_population
def roulette_selection(self, ga):
"""Roulette selection works based off of how strong the fitness is of the