def fitness(p, x_train, y_train, x_test, y_test):
# Init fitness
fitness_indi = 0
N = Individual()
p = N.individual_decode(p)
N = N.individual_model(p,
num_class=2,
x_train=x_train,
y_train=y_train,
x_test=x_test,
y_test=y_test)
fitness_indi = N.evaluate(x=x_test, y=y_test, verbose=0)[1]
return fitness_indi
def crossover(self, parent_1: Individual,
parent_2: Individual) -> Individual:
"""Crossover two parents using the Periodic crossover with Intersections (PIX) algorithm,
as defined in Vidal et al. (2011)."""
# logger.debug("Beginning crossover")
# logger.debug(f"Par 1 chrom: {parent_1.giant_tour_chromosome}")
# logger.debug(f"Par 2 chrom: {parent_2.giant_tour_chromosome}")
child_vehicle_type_chromosome: Union[None, Dict[int, List[int]]] = {}
child_giant_tour_chromosome: Dict[int, List[Location]] = {}
for vehicle_type in self.possible_vehicle_types:
child_giant_tour_chromosome[vehicle_type.data_index] = []
num_vehicle_types = len(self.possible_vehicle_types)
# Step 0: Inheritance Rule
# Figure out which tours are inherited from P1, which from P2 and which others are mixed
# In Vidal's paper, the tours are per-period and per-depot, so each pairing needs to be accounted for.
# In my implementation, there are only the vehicle_index types to account for.
if num_vehicle_types > 1:
cuts = sample(range(num_vehicle_types), 2)
if cuts[0] < cuts[1]:
n_1 = cuts[0]
n_2 = cuts[1]
else:
n_1 = cuts[1]
n_2 = cuts[0]
# Put the vehicle_index types into a randomly ordered list
vehicle_type_list = list(self.possible_vehicle_types)
shuffle(vehicle_type_list)
# Divide up the vehicle_index types into the sets to be inherited
set_1 = vehicle_type_list[0:n_1]
set_2 = vehicle_type_list[n_1:n_2]
set_mix = vehicle_type_list[n_2:num_vehicle_types]
else:
# If there is only one vehicle type, it goes into the mixed set
set_1 = []
set_2 = []
set_mix = list(self.possible_vehicle_types)
# logger.debug(f"Crossover sets: {set_1},\t{set_2},\t{set_mix}")
# Step 1: Inherit data from P1
# Set 1 inherits the whole tours
for vehicle_type in set_1:
if parent_1.giant_tour_chromosome.get(
vehicle_type.data_index) is None:
continue
child_giant_tour_chromosome[vehicle_type.data_index] = \
[copy(stop) for stop in parent_1.giant_tour_chromosome[vehicle_type.data_index]]
for child in child_giant_tour_chromosome[vehicle_type.data_index]:
append_to_chromosome(child_vehicle_type_chromosome,
child.data_index, vehicle_type, False)
# Mixed set inherits pieces of the tours
for vehicle_type in set_mix:
if parent_1.giant_tour_chromosome.get(
vehicle_type.data_index) is None:
continue
tour_length = len(
parent_1.giant_tour_chromosome[vehicle_type.data_index])
cut_a = randint(0, tour_length)
cut_b = cut_a
if tour_length > 1:
while cut_b == cut_a:
# logger.debug(f"{tour_length}: {cut_a}, {cut_b}")
cut_b = randint(0, tour_length)
if cut_a < cut_b:
child_tour = [
copy(stop) for stop in parent_1.giant_tour_chromosome[
vehicle_type.data_index][cut_a:cut_b]
]
else:
child_tour = [
copy(stop) for stop in [
*parent_1.giant_tour_chromosome[
vehicle_type.data_index][0:cut_b],
*parent_1.giant_tour_chromosome[
vehicle_type.data_index][cut_a:tour_length]
]
]
child_giant_tour_chromosome[vehicle_type.data_index] = child_tour
for child in child_giant_tour_chromosome[vehicle_type.data_index]:
append_to_chromosome(child_vehicle_type_chromosome,
child.data_index, vehicle_type, False)
# logger.debug(f"Data inherited from P1")
# all_stops = [stop_t for vehicle_type_t in [*set_1, *set_mix] for stop_t in
# parent_1.giant_tour_chromosome.get(vehicle_type_t.data_index)]
# if len(child_giant_tour_chromosome.keys()) == 0 and len(all_stops) > 0:
# raise ValueError(f"No keys in child chromosome. All stops {all_stops}")
# Step 2: Inherit data from P2
# For all vehicle_index types in set 2 and mix, loop through the customers in parent 2.
# If the customer either has a matching vehicle_index type or none in the child's vehicle_index chromosome,
# add it to this type's tour. Recall that the vehicle_index types are in a random order in the sets.
# This allows customers to be reassigned between vehicle_index types, while vaguely keeping the parent's order.
for vehicle_type in [*set_2, *set_mix]:
if parent_2.giant_tour_chromosome.get(vehicle_type.data_index):
for stop in parent_2.giant_tour_chromosome[
vehicle_type.data_index]:
customer_vehicles = child_vehicle_type_chromosome.get(
stop.data_index)
if customer_vehicles is None or vehicle_type in customer_vehicles:
append_to_chromosome(child_giant_tour_chromosome,
vehicle_type.data_index, stop)
append_to_chromosome(child_vehicle_type_chromosome,
stop.data_index, vehicle_type,
False)
# logger.debug(f"Data inherited from P2")
# logger.debug(f"Child chrom: {child_giant_tour_chromosome}")
# Step 3: Complete customer services
child = Individual(
child_giant_tour_chromosome,
vehicle_type_chromosome=child_vehicle_type_chromosome,
possible_locations=self.possible_locations)
# child.update_all_routes_location_indices()
# child.complete_customer_services(self.allow_split_deliveries)
# if len(child_giant_tour_chromosome.keys()) == 0:
# raise ValueError(f"No keys in child chromosome.")
# child.complete_customer_services_slow()
child.evaluate()
# logger.debug(f"Completed customer services")
# Create and return the child
return child
