粒子群算法求解车间调度问题python代码
时间: 2023-08-25 18:05:51 浏览: 90
好的,我可以给你一份 Python 代码,用粒子群算法解决车间调度问题:
```
import random
class PSO:
def __init__(self, iterations, swarm_size, particles_dim, max_velocity):
self.iterations = iterations
self.swarm_size = swarm_size
self.particles_dim = particles_dim
self.max_velocity = max_velocity
self.w = 0.729
self.c1 = 1.49445
self.c2 = 1.49445
self.gbest_fitness = None
self.gbest_position = None
self.swarm_position = []
self.swarm_velocity = []
self.pbest_position = []
self.pbest_fitness = []
for i in range(swarm_size):
position = [random.randint(0, particles_dim - 1) for i in range(particles_dim)]
velocity = [random.uniform(-max_velocity, max_velocity) for i in range(particles_dim)]
self.swarm_position.append(position)
self.swarm_velocity.append(velocity)
self.pbest_position.append(position)
self.pbest_fitness.append(float('inf'))
def run(self, eval_func):
for i in range(self.iterations):
for j in range(self.swarm_size):
fitness = eval_func(self.swarm_position[j])
if fitness < self.pbest_fitness[j]:
self.pbest_fitness[j] = fitness
self.pbest_position[j] = self.swarm_position[j]
if self.gbest_fitness == None or fitness < self.gbest_fitness:
self.gbest_fitness = fitness
self.gbest_position = self.swarm_position[j]
for j in range(self.swarm_size):
for k in range(self.particles_dim):
r1 = random.random()
r2 = random.random()
vel_cognitive = self.c1 * r1 * (self.pbest_position[j][k] - self.swarm_position[j][k])
vel_social = self.c2 * r2 * (self.gbest_position[k] - self.swarm_position[j][k])
self.swarm_velocity[j][k] = self.w * self.swarm_velocity[j][k] + vel_cognitive + vel_social
if self.swarm_velocity[j][k] > self.max_velocity:
self.swarm_velocity[j][k] = self.max_velocity
elif self.swarm_velocity[j][k] < -self.max_velocity:
self.swarm_velocity[j][k] = -self.max_velocity
self.swarm_position[j][k] += self.swarm_velocity[j][k]
return self.gbest_fitness, self.gbest_position
```
这里是一个简单的使用案例:
```
def eval_func(position):
# 对 position 进行车间调度,计算 makespan,并返回
return makespan
pso = PSO(iterations=100, swarm_size=50, particles_dim=10, max_velocity=5)
best_fitness, best_position = pso.run(eval_func)
print('最短完成时间为:', best_fitness)
print('最佳车间调度为:', best_position)
```
你需要自己编写 eval_func 函数来计算 makespan。注意,这里用到的是“粒子群算法(Particle Swarm Optimization,PSO)”,不是“蚁群算法(Ant Colony Optimization,ACO)”。如果你需要 ACO 的相关代码的话,请告诉我。
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