给出符合下列要求的代码,1.初始化种群:第一个解决方案:由NEH2规则产生,选择完工时间最小的位置。第二个解决方案:对于每个作业𝑗,将其插入到所有工厂中所有可能的位置,然后选择总能耗最小的位置。第三个解决方案:对于一个作业𝑗,将其插入到所有工厂中的所有可能的位置,并选择具有最小总能耗和最小最大完工时间的位置。其余的解决方案随机产生,以保持种群的多样性。编码规则如下:有一组列表𝝅={𝝅1,...,𝝅𝑓,…,𝝅𝐹},其中一个列表𝝅𝑓表示分配给工厂𝑓的部分作业,该列表的作业序列表示第一阶段的作业处理序列。解码机制如下:对于第一阶段的列表𝝅,每个列表𝝅𝑓中的作业被分配给工厂𝑓中的第一台可用机器;在下一阶段,将根据上一阶段的完成时间重新排序作业;另外,如果某些作业在当前阶段有相同的开始时间,那么它们将按照与前一个阶段相同的顺序排列。
时间: 2024-02-21 16:58:18 浏览: 62
以下是符合要求的 Python 代码:
```python
import random
# 初始化种群
def initialize_population(num_individuals, num_jobs, num_factories):
population = []
# 第一个解决方案:使用 NEH2 规则产生
neh_sol = neh2(num_jobs, num_factories)
neh_fitness = calculate_fitness(neh_sol)
population.append((neh_sol, neh_fitness))
# 第二个解决方案:对于每个作业𝑗,将其插入到所有工厂中所有可能的位置,然后选择总能耗最小的位置
for i in range(num_individuals//3):
solution = []
for job in range(num_jobs):
costs = []
for factory in range(num_factories):
for pos in range(len(solution[factory])+1):
new_solution = solution.copy()
new_solution[factory].insert(pos, job)
cost = calculate_fitness(new_solution)
costs.append((cost, factory, pos))
min_cost, min_factory, min_pos = min(costs)
solution[min_factory].insert(min_pos, job)
fitness = calculate_fitness(solution)
population.append((solution, fitness))
# 第三个解决方案:对于一个作业𝑗,将其插入到所有工厂中的所有可能的位置,并选择具有最小总能耗和最小最大完工时间的位置
for i in range(num_individuals//3):
solution = []
for job in range(num_jobs):
costs = []
for factory in range(num_factories):
for pos in range(len(solution[factory])+1):
new_solution = solution.copy()
new_solution[factory].insert(pos, job)
cost = calculate_fitness(new_solution)
makespan = calculate_makespan(new_solution)
costs.append((cost, makespan, factory, pos))
min_cost, min_makespan, min_factory, min_pos = min(costs)
solution[min_factory].insert(min_pos, job)
fitness = calculate_fitness(solution)
population.append((solution, fitness))
# 其余的解决方案随机产生,以保持种群的多样性
for i in range(num_individuals - len(population)):
solution = []
for job in range(num_jobs):
factory = random.randint(0, num_factories-1)
pos = random.randint(0, len(solution[factory]))
solution[factory].insert(pos, job)
fitness = calculate_fitness(solution)
population.append((solution, fitness))
return population
# NEH2 规则
def neh2(num_jobs, num_factories):
jobs = list(range(num_jobs))
job_times = [random.randint(1, 10) for _ in range(num_jobs)]
makespans = []
for i in range(num_jobs):
job_order = [jobs[i]] + makespans
factory_times = [sum(job_times[j] for j in job_order[:k+1]) for k in range(num_factories)]
total_time = factory_times[-1]
makespans.append((job_order, total_time))
neh_order = [job for job, _ in sorted(makespans, key=lambda x: x[1])]
solution = [[] for _ in range(num_factories)]
for i, job in enumerate(neh_order):
solution[i % num_factories].append(job)
return solution
# 计算适应度函数值
def calculate_fitness(solution):
total_cost = 0
for factory in solution:
factory_cost = 0
machine_times = [0] * len(factory)
for job in factory:
job_time = job_times[job]
machine_times = [max(machine_times[i], machine_times[i-1]) + job_time for i in range(1, len(machine_times))]
machine_times[0] += job_time
factory_cost += sum(machine_times)
total_cost += factory_cost
return total_cost
# 计算最大完工时间
def calculate_makespan(solution):
makespans = []
for factory in solution:
machine_times = [0] * len(factory)
for job in factory:
job_time = job_times[job]
machine_times = [max(machine_times[i], machine_times[i-1]) + job_time for i in range(1, len(machine_times))]
machine_times[0] += job_time
makespans.append(max(machine_times))
return max(makespans)
```
其中 `num_individuals` 表示种群大小,`num_jobs` 表示作业数量,`num_factories` 表示工厂数量,`job_times` 表示每个作业的处理时间。
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