python实现JADE算法
时间: 2023-08-01 16:12:41 浏览: 67
JADE(Adaptive Differential Evolution with Optional External Archive)是一种高效的差分进化算法,可以用于求解函数最优化问题。下面是一个基于Python的JADE算法的实现示例:
```python
import numpy as np
def JADE(objective_func, bounds, population_size=50, max_generations=100,
c=0.1, p=0.05, archive_size=100, mutation_factor=0.5):
# 初始化种群和参数
population = np.random.uniform(bounds[0], bounds[1], (population_size, len(bounds)))
archive = []
archive_fitness = []
best_fitness = np.inf
best_solution = None
# 迭代演化
for generation in range(max_generations):
for i in range(population_size):
# 随机选择3个不同的父个体
candidates = np.arange(population_size)
np.random.shuffle(candidates)
a, b, c = candidates[:3]
# 变异操作
mutant = population[a] + mutation_factor * (population[b] - population[c])
# 交叉操作
crossover = np.random.rand(len(bounds)) < c
trial = np.where(crossover, mutant, population[i])
# 评估目标函数值
fitness_trial = objective_func(trial)
fitness_current = objective_func(population[i])
# 更新最优解
if fitness_trial < best_fitness:
best_solution = trial
best_fitness = fitness_trial
# 更新种群和归档
if fitness_trial < fitness_current or np.random.rand() < p:
population[i] = trial
if fitness_trial < fitness_current:
archive.append(trial)
archive_fitness.append(fitness_trial)
# 适应度排序,剔除过多的个体
if len(archive) > archive_size:
sorted_indices = np.argsort(archive_fitness)
archive = [archive[i] for i in sorted_indices[:archive_size]]
archive_fitness = [archive_fitness[i] for i in sorted_indices[:archive_size]]
return best_solution, best_fitness
```
在上述代码中,`objective_func` 是需要优化的目标函数,`bounds` 是每个变量的取值范围。`population_size` 是种群的大小,`max_generations` 是演化的最大代数,`c` 是交叉概率,`p` 是自适应概率,`archive_size` 是归档的大小,`mutation_factor` 是变异因子。
你可以根据自己的问题定义相应的目标函数,并调用 `JADE` 函数进行优化。该函数返回最优解和最优解对应的目标函数值。
请注意,这只是一个简单的示例,实际应用中可能需要根据具体问题进行适当的改进和调整。