This commit is contained in:
weixin_46229132 2025-03-28 15:13:23 +08:00
parent a375832b6c
commit 656e822528
2 changed files with 1 additions and 302 deletions

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@ -196,29 +196,7 @@ class TSP(object):
''' '''
for epoch in range(num_epochs): for epoch in range(num_epochs):
await self.train_for_one_epoch() await self.train_for_one_epoch()
if display:
self.draw(epoch)
def draw(self, epoch):
'''
绘图
'''
_ = plt.scatter(*self.cities)
for fr, to in zip(self.best_path[:-1], self.best_path[1:]):
x1, y1 = self.cities[:, fr]
x2, y2 = self.cities[:, to]
dx, dy = x2-x1, y2-y1
plt.arrow(x1, y1, dx, dy, width=0.01*min(self.map_size),
edgecolor='orange', facecolor='white', animated=True,
length_includes_head=True)
nrs = np.exp(self.qualities)
for i in range(self.num_cities):
nrs[i, i] = 0
gap = np.abs(np.exp(self.normalizers) - nrs.sum(-1)).mean()
plt.title(
f'epoch {epoch}: path length = {self.best_path_length:.2f}, normalizer error = {gap:.3f}')
plt.savefig('tsp.png')
plt.show()
async def main(): async def main():
# 创建TSP实例 # 创建TSP实例
@ -231,7 +209,6 @@ async def main():
print(f"最优路径: {tsp.best_path}") print(f"最优路径: {tsp.best_path}")
print(f"路径长度: {tsp.best_path_length:.2f}") print(f"路径长度: {tsp.best_path_length:.2f}")
if __name__ == "__main__":
if __name__ == '__main__':
# 使用asyncio.run()运行异步主函数 # 使用asyncio.run()运行异步主函数
asyncio.run(main()) asyncio.run(main())

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@ -1,278 +0,0 @@
import pylab as plt
import numpy as np
import asyncio
from typing import List, Tuple, Dict, Any
import yaml
class mTSP:
'''
Q-Learning 求解多旅行商问题
基于TSP.py修改增加了多旅行商的支持
'''
def __init__(self,
num_cities: int = 15,
num_drones: int = 3,
map_size: Tuple[float, float] = (800.0, 600.0),
alpha: float = 2,
beta: float = 1,
learning_rate: float = 0.001,
eps: float = 0.1,
params_file: str = 'params2.yml'):
'''
Args:
num_cities (int): 实际城市数目不包括虚拟起点
num_drones (int): 无人机数量
map_size (int, int): 地图尺寸
alpha (float): 一个超参值越大越优先探索最近的点
beta (float): 一个超参值越大越优先探索可能导向总距离最优的点
learning_rate (float) 学习率
eps (float): 探索率值越大探索性越强但越难收敛
params_file (str): 参数文件路径
'''
self.num_cities = num_cities
self.num_drones = num_drones
self.map_size = map_size
self.alpha = alpha
self.beta = beta
self.eps = eps
self.learning_rate = learning_rate
# 加载参数
with open(params_file, 'r', encoding='utf-8') as file:
self.params = yaml.safe_load(file)
# 生成城市和虚拟起点
self.cities = self.generate_cities()
self.to_process_idx = self.generate_start_points()
# 计算距离矩阵
self.distances = self.get_dist_matrix()
self.mean_distance = self.distances.mean()
# Q-learning相关
self.qualities = np.zeros([self.total_cities, self.total_cities])
self.normalizers = np.zeros(self.total_cities)
self.best_path = None
self.best_path_length = np.inf
# 计算每个点的飞行时间和基站时间
self.rectangles = self.calculate_rectangles()
@property
def total_cities(self) -> int:
"""总城市数(包括虚拟起点)"""
return self.num_cities + self.num_drones - 1
def generate_cities(self) -> np.ndarray:
'''生成城市坐标'''
max_width, max_height = self.map_size
cities = np.random.random([2, self.num_cities]) \
* np.array([max_width, max_height]).reshape(2, -1)
return cities
def generate_start_points(self) -> List[int]:
'''生成起点索引列表'''
# 添加虚拟起点
virtual_starts = np.zeros([2, self.num_drones - 1])
self.cities = np.hstack([self.cities, virtual_starts])
return list(range(self.num_cities, self.total_cities))
def get_dist_matrix(self) -> np.ndarray:
'''计算距离矩阵'''
dist_matrix = np.zeros([self.total_cities, self.total_cities])
for i in range(self.total_cities):
for j in range(self.total_cities):
if i == j:
dist_matrix[i, j] = np.inf
continue
xi, xj = self.cities[0, i], self.cities[0, j]
yi, yj = self.cities[1, i], self.cities[1, j]
dist_matrix[i, j] = np.sqrt((xi-xj)**2 + (yi-yj)**2)
# 设置起点之间的距离为无穷大
for i in self.to_process_idx:
for j in self.to_process_idx:
if i != j:
dist_matrix[i, j] = np.inf
return dist_matrix
def calculate_rectangles(self) -> List[Dict[str, Any]]:
'''计算每个点的飞行时间和基站时间'''
rectangles = []
for i in range(self.num_cities):
d = 1.0 # 这里简化处理,实际应该根据区域大小计算
rho_time_limit = (self.params['flight_time_factor'] - self.params['trans_time_factor']) / \
(self.params['comp_time_factor'] - self.params['trans_time_factor'])
rho_energy_limit = (self.params['battery_energy_capacity'] -
self.params['flight_energy_factor'] * d -
self.params['trans_energy_factor'] * d) / \
(self.params['comp_energy_factor'] * d -
self.params['trans_energy_factor'] * d)
rho = min(rho_time_limit, rho_energy_limit)
flight_time = self.params['flight_time_factor'] * d
bs_time = self.params['bs_time_factor'] * (1 - rho) * d
rectangles.append({
'flight_time': flight_time,
'bs_time': bs_time,
'center': (self.cities[0, i], self.cities[1, i])
})
return rectangles
def rollout(self, start_city_id: int = None) -> Tuple[List[int], List[float], List[float]]:
'''执行一次路径探索'''
cities_visited = []
action_probs = []
if start_city_id is None:
start_city_id = np.random.choice(self.to_process_idx)
current_city_id = start_city_id
cities_visited.append(current_city_id)
while len(cities_visited) < self.total_cities:
current_city_id, action_prob = self.choose_next_city(cities_visited)
cities_visited.append(current_city_id)
action_probs.append(action_prob)
# 返回起点
cities_visited.append(cities_visited[0])
action_probs.append(1.0)
path_length = self.calc_path_length(cities_visited)
if path_length < self.best_path_length:
self.best_path = cities_visited
self.best_path_length = path_length
rewards = self.calc_path_rewards(cities_visited, path_length)
return cities_visited, action_probs, rewards
def choose_next_city(self, cities_visited: List[int]) -> Tuple[int, float]:
'''选择下一个城市'''
current_city_id = cities_visited[-1]
probabilities = np.exp(self.qualities[current_city_id])
# 将已访问的城市概率设为0
for city_visited in cities_visited:
probabilities[city_visited] = 0
# 计算softmax概率
probabilities = probabilities/probabilities.sum()
if np.random.random() < self.eps:
next_city_id = np.random.choice(range(len(probabilities)), p=probabilities)
else:
next_city_id = probabilities.argmax()
if probabilities.argmax() == next_city_id:
action_prob = probabilities[next_city_id]*self.eps + (1-self.eps)
else:
action_prob = probabilities[next_city_id]*self.eps
return next_city_id, action_prob
def calc_path_length(self, path: List[int]) -> float:
'''计算路径长度'''
# 将路径分成多个子路径
car_paths = []
found_start_points = []
# 找到所有起点
for i, city in enumerate(path):
if city in self.to_process_idx:
found_start_points.append(i)
# 根据起点分割路径
for i in range(len(found_start_points)-1):
start_idx = found_start_points[i]
end_idx = found_start_points[i+1]
car_paths.append(path[start_idx:end_idx+1])
# 计算每个子路径的时间
T_k_list = []
for car_path in car_paths:
flight_time = 0
bs_time = 0
car_time = 0
# 计算飞行时间和基站时间
for point in car_path:
if point not in self.to_process_idx:
flight_time += self.rectangles[point]['flight_time']
bs_time += self.rectangles[point]['bs_time']
# 计算车辆时间
for i in range(len(car_path)-1):
if car_path[i] not in self.to_process_idx and car_path[i+1] not in self.to_process_idx:
car_time += self.distances[car_path[i], car_path[i+1]] * self.params['car_time_factor']
# 计算总时间
system_time = max(flight_time + car_time, bs_time)
T_k_list.append(system_time)
return max(T_k_list)
def calc_path_rewards(self, path: List[int], path_length: float) -> List[float]:
'''计算路径奖励'''
rewards = []
for fr, to in zip(path[:-1], path[1:]):
dist = self.distances[fr, to]
reward = (self.mean_distance/path_length)**self.beta
reward = reward*(self.mean_distance/dist)**self.alpha
rewards.append(np.log(reward))
return rewards
def calc_updates_for_one_rollout(self, path: List[int], action_probs: List[float],
rewards: List[float]) -> Tuple[List[float], List[float]]:
'''计算一次rollout的更新值'''
qualities = []
normalizers = []
for fr, to, reward, action_prob in zip(path[:-1], path[1:], rewards, action_probs):
log_action_probability = np.log(action_prob)
qualities.append(- reward*log_action_probability)
normalizers.append(- (reward + 1)*log_action_probability)
return qualities, normalizers
def update(self, path: List[int], new_qualities: List[float],
new_normalizers: List[float]) -> None:
'''更新Q值和normalizer'''
lr = self.learning_rate
for fr, to, new_quality, new_normalizer in zip(
path[:-1], path[1:], new_qualities, new_normalizers):
self.normalizers[fr] = (1-lr)*self.normalizers[fr] + lr*new_normalizer
self.qualities[fr, to] = (1-lr)*self.qualities[fr, to] + lr*new_quality
async def train_for_one_rollout(self, start_city_id: int) -> None:
'''训练一次rollout'''
path, action_probs, rewards = self.rollout(start_city_id)
new_qualities, new_normalizers = self.calc_updates_for_one_rollout(
path, action_probs, rewards)
self.update(path, new_qualities, new_normalizers)
async def train_for_one_epoch(self) -> None:
'''训练一个epoch'''
tasks = [self.train_for_one_rollout(start_city_id)
for start_city_id in self.to_process_idx]
await asyncio.gather(*tasks)
async def train(self, num_epochs: int = 1000, display: bool = True) -> None:
'''训练过程'''
for epoch in range(num_epochs):
await self.train_for_one_epoch()
if display and epoch % 100 == 0:
print(f"Epoch {epoch}: Best path length = {self.best_path_length:.2f}")
async def main():
# 创建mTSP实例
mtsp = mTSP(num_cities=12, num_drones=3)
# 训练模型
await mtsp.train(200, display=True)
# 输出最终路径
print(f"\n最优路径: {mtsp.best_path}")
print(f"路径长度: {mtsp.best_path_length:.2f}")
if __name__ == '__main__':
asyncio.run(main())