def branch_bound_search(order):
branch_bound_matrix, point_list = build_bb_matrix(order)
points = sorted(set(point_list), key=point_list.index)
points = find_common_point(points, point_list)
start_point = startpoint
reduced_matrix, cost = reduce_matrix(branch_bound_matrix)
start_node = TreeNode(startpoint, reduced_matrix, cost)
start_node.set_id(0)
last_node = start_node
queue = Queue.PriorityQueue()
# queue.put(start_node)
nn_path, _, _ = nn_search(order)
upper_bound_cost = find_upper_bound(nn_path, point_list, start_node)
# print upper_bound_cost
id = start_node.get_id()
for point in points:
# if point == endpoint:
# continue
child = build_tree_node(point, start_node, point_list)
id = id + 1
child.set_id(id)
if child.get_cost() > upper_bound_cost:
continue
queue.put(child)
candidate = nn_path
paths = {}
id = 0
start = time.time()
last_matrix = None
visited = []
while (queue.qsize() > 0):
if (time.time() > start + 30):
print('Time Out!')
return candidate, calculate_path_distance(candidate), last_matrix
parent_node = queue.get()
visited.append(parent_node.get_point())
if (paths.has_key(parent_node)):
path = paths[parent_node]
else:
path = []
path.append(start_point)
path.append(parent_node.get_point())
parent_level = parent_node.get_level()
for point in points:
# neighbor = get_neighbor(point, point_list)
if point == parent_node.get_point(
) or point in path or point == endpoint:
continue
# if(parent_node.get_point() <> neighbor):
id = id + 1
child = build_tree_node(point, parent_node, point_list)
child.set_level(parent_level + 1)
child.set_id(id)
parent_node.add_child(child)
# visited.append(point)
path.append(child.get_point())
# print len(path)
# else:
# continue
if (len(path) == len(nn_path) - 1):
if (child.get_cost() > INFINITY - 2000):
path.remove(child.get_point())
continue
path.append(endpoint)
candidate = path
return candidate, calculate_path_distance(
candidate), last_matrix
else:
# print (len(path))
paths[child] = copy.deepcopy(path)
path.remove(child.get_point())
last_matrix = child.get_matrix()
if (child.get_cost() >= upper_bound_cost):
continue
queue.put(child)
path.append(endpoint)
return candidate, calculate_path_distance(candidate), last_matrix
