def best_cost_route_crossover(offsprings, nodes, rate=0.5):
new_offsprings = []
half = int(len(offsprings)/2)
for (indv1, indv2) in zip (offsprings[0:half], offsprings[half:]):
tmp1 = copy.deepcopy(indv1)
tmp2 = copy.deepcopy(indv2)
if random.random() < rate:
(tmp1.chromosome, tmp2.chromosome) = \
_best_cost_route_crossover(nodes, indv1.chromosome, indv2.chromosome)
tmp1.chromosome = remove_null_route(tmp1.chromosome) # Remove the route which has no nodes
tmp2.chromosome = remove_null_route(tmp2.chromosome)
new_offsprings.append(tmp1)
new_offsprings.append(tmp2)
return new_offsprings
def _insertion(chromosome, nodes, rate=0.02):
size = len(_flatten(chromosome))
for _ in range(size):
if random.random() < rate:
_random_choice_and_reinsert(chromosome, nodes)
chromosome = remove_null_route(chromosome)
return chromosome
def insertion(offsprings, nodes, rate=0.2, irate=0.02):
new_offsprings = []
for indv in offsprings:
tmp = copy.deepcopy(indv)
if random.random() < rate:
tmp.chromosome = _insertion(indv.chromosome, nodes, irate)
tmp.chromosome = remove_null_route(tmp.chromosome) # Remove the route which has no nodes
new_offsprings.append(tmp)
return new_offsprings
def exchange_chromosome(nodes, ch1):
deliver_size = nodes.get_deliver_customer_size()
no_Null_Chromosome = copy.deepcopy(remove_null_route(ch1))
if len(no_Null_Chromosome) == 15:
if random.random() > 0.5:
# two route exchange
two_index = random.sample(range(0, len(no_Null_Chromosome)), 2)
route1 = no_Null_Chromosome[two_index[0]]
route2 = no_Null_Chromosome[two_index[1]]
raw_index1 = ch1.index(route1)
raw_index2 = ch1.index(route2)
reversed_route_1 = {
node_id: index
for (index, node_id) in route1.items()
}
reversed_route_2 = {
node_id: index
for (index, node_id) in route2.items()
}
route_deliver_nodes_1 = np.sort(
np.array(list(
reversed_route_1.keys())))[:int(len(reversed_route_1) / 2)]
route_deliver_nodes_2 = np.sort(
np.array(list(
reversed_route_2.keys())))[:int(len(reversed_route_2) / 2)]
exchange_start_node_1 = random.sample(
route_deliver_nodes_1.tolist(), 1)[0]
exchange_start_node_2 = random.sample(
route_deliver_nodes_2.tolist(), 1)[0]
exchange_end_node_1 = exchange_start_node_1 + deliver_size
exchange_end_node_2 = exchange_start_node_2 + deliver_size
tmp = route1[reversed_route_1[exchange_start_node_1]]
route1[reversed_route_1[exchange_start_node_1]] = route2[
reversed_route_2[exchange_start_node_2]]
route2[reversed_route_2[exchange_start_node_2]] = tmp
tmp = route1[reversed_route_1[exchange_end_node_1]]
route1[reversed_route_1[exchange_end_node_1]] = route2[
reversed_route_2[exchange_end_node_2]]
route2[reversed_route_2[exchange_end_node_2]] = tmp
ch1[raw_index1] = route1
ch1[raw_index2] = route2
else:
# delete elements of one route and add them to another route
two_index = random.sample(range(0, len(no_Null_Chromosome)), 2)
route1 = no_Null_Chromosome[two_index[0]]
route2 = no_Null_Chromosome[two_index[1]]
raw_index1 = ch1.index(route1)
raw_index2 = ch1.index(route2)
route_nodes_1 = list(route1.values())
route_nodes_2 = list(route2.values())
exchange_node1 = random.sample(route_nodes_1, 1)[0]
if exchange_node1 <= deliver_size:
exchange_start_node_1 = exchange_node1
exchange_end_node_1 = exchange_node1 + deliver_size
else:
exchange_start_node_1 = exchange_node1 - deliver_size
exchange_end_node_1 = exchange_node1
route_nodes_1.remove(exchange_start_node_1)
route_nodes_1.remove(exchange_end_node_1)
route2_size = len(route_nodes_2)
random_insert = random.randint(0, route2_size)
route_nodes_2.insert(random_insert, exchange_start_node_1)
insert_index = route_nodes_2.index(exchange_start_node_1)
route_nodes_2.insert(
random.randint(insert_index + 1, len(route_nodes_2)),
exchange_end_node_1)
route1 = {(i + 1): int(node_id)
for (i, node_id) in enumerate(route_nodes_1)}
route2 = {(i + 1): int(node_id)
for (i, node_id) in enumerate(route_nodes_2)}
ch1[raw_index1] = route1
ch1[raw_index2] = route2
elif len(no_Null_Chromosome) < 15 and random.random() > 0.9:
route = no_Null_Chromosome[0]
lengths = [len(ch1[i]) for i in range(len(ch1))]
raw_index = ch1.index(route)
route_nodes = list(route.values())
exchange_node = random.sample(route_nodes, 1)[0]
if exchange_node <= deliver_size:
exchange_start_node_1 = exchange_node
exchange_end_node_1 = exchange_node + deliver_size
else:
exchange_start_node_1 = exchange_node - deliver_size
exchange_end_node_1 = exchange_node
route_nodes.remove(exchange_start_node_1)
route_nodes.remove(exchange_end_node_1)
route = {(index + 1): node_id
for index, node_id in enumerate(route_nodes)}
ch1[raw_index] = route
added_route = [exchange_start_node_1, exchange_end_node_1]
added_route = {(index + 1): int(node_id)
for index, node_id in enumerate(added_route)}
add_index = lengths.index(0)
'''if raw_index == 0:
ch1[raw_index + 1] = added_route
elif raw_index == (len(ch1) - 1):
ch1[raw_index - 1] = added_route
else:
ch1[raw_index + 1] = added_route'''
ch1[add_index] = added_route
return ch1