请基于蚁群算法并用python结合matplotlib写一个在二维栅格图的避障的最优路径的可视化代码
时间: 2023-06-13 17:02:28 浏览: 175
好的,以下是使用蚁群算法实现在二维栅格图上的避障最优路径可视化的Python代码:
```python
import random
import math
import matplotlib.pyplot as plt
# 定义栅格地图尺寸和障碍物位置
MAP_WIDTH = 50
MAP_HEIGHT = 50
OBSTACLE_LIST = [(25, 25), (26, 25), (27, 25), (28, 25)]
# 定义蚂蚁数量
ANT_COUNT = 50
# 定义迭代次数
ITERATION_COUNT = 200
# 定义信息素挥发和更新速率
PHEROMONE_EVAPORATION = 0.3
PHEROMONE_UPDATE_RATE = 0.8
# 定义信息素和启发式函数的权重
PHEROMONE_WEIGHT = 1.0
HEURISTIC_WEIGHT = 2.0
# 定义启发式函数的参数
HEURISTIC_EXPONENT = 2.0
class Ant:
def __init__(self):
self.path = [(0, 0)]
self.visited = set()
self.visited.add((0, 0))
def move(self, pheromone_map):
current_position = self.path[-1]
neighbors = self.get_neighbors(current_position)
probabilities = []
total_probability = 0.0
for neighbor in neighbors:
if neighbor in self.visited:
continue
probability = self.calculate_probability(current_position, neighbor, pheromone_map)
probabilities.append((neighbor, probability))
total_probability += probability
if total_probability == 0.0:
return
probabilities = [(n, p / total_probability) for n, p in probabilities]
target, _ = random.choices(probabilities)[0]
self.path.append(target)
self.visited.add(target)
def get_neighbors(self, position):
x, y = position
neighbors = []
if x > 0:
neighbors.append((x - 1, y))
if x < MAP_WIDTH - 1:
neighbors.append((x + 1, y))
if y > 0:
neighbors.append((x, y - 1))
if y < MAP_HEIGHT - 1:
neighbors.append((x, y + 1))
return neighbors
def calculate_probability(self, current_position, neighbor, pheromone_map):
pheromone = pheromone_map[neighbor[0]][neighbor[1]]
distance = self.calculate_distance(current_position, neighbor)
heuristic = self.calculate_heuristic(neighbor)
probability = math.pow(pheromone, PHEROMONE_WEIGHT) * math.pow(heuristic, HEURISTIC_WEIGHT)
probability /= math.pow(distance, HEURISTIC_EXPONENT)
return probability
def calculate_distance(self, position1, position2):
x1, y1 = position1
x2, y2 = position2
return math.sqrt((x1 - x2) ** 2 + (y1 - y2) ** 2)
def calculate_heuristic(self, position):
x, y = position
min_distance = float('inf')
for obstacle in OBSTACLE_LIST:
distance = self.calculate_distance(position, obstacle)
if distance < min_distance:
min_distance = distance
return 1.0 / (min_distance + 1.0)
def initialize_pheromone_map():
return [[1.0] * MAP_HEIGHT for _ in range(MAP_WIDTH)]
def update_pheromone_map(pheromone_map, ant_list):
for i in range(len(pheromone_map)):
for j in range(len(pheromone_map[0])):
pheromone_map[i][j] *= PHEROMONE_EVAPORATION
for ant in ant_list:
for i in range(len(ant.path) - 1):
position1 = ant.path[i]
position2 = ant.path[i + 1]
pheromone_map[position1[0]][position1[1]] += PHEROMONE_UPDATE_RATE
def run_ant_colony_optimization():
ant_list = [Ant() for _ in range(ANT_COUNT)]
pheromone_map = initialize_pheromone_map()
best_path = []
best_distance = float('inf')
for i in range(ITERATION_COUNT):
for ant in ant_list:
ant.move(pheromone_map)
update_pheromone_map(pheromone_map, ant_list)
for ant in ant_list:
if ant.path[-1] == (MAP_WIDTH - 1, MAP_HEIGHT - 1):
distance = len(ant.path)
if distance < best_distance:
best_distance = distance
best_path = ant.path
return best_path
def plot_path(path):
obstacle_x, obstacle_y = zip(*OBSTACLE_LIST)
path_x, path_y = zip(*path)
plt.scatter(obstacle_x, obstacle_y, color='red')
plt.plot(path_x, path_y, color='blue', linewidth=2.0)
plt.xlim(0, MAP_WIDTH)
plt.ylim(0, MAP_HEIGHT)
plt.show()
if __name__ == '__main__':
best_path = run_ant_colony_optimization()
plot_path(best_path)
```
这段代码将生成一个二维栅格图,其中红点表示障碍物,蓝线表示在避开障碍物的情况下最优路径。您可以根据需要调整栅格地图的尺寸、障碍物位置、蚂蚁数量、迭代次数、信息素挥发和更新速率、信息素和启发式函数的权重以及启发式函数的参数。
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