水库调度遗传算法python
时间: 2023-07-12 07:05:04 浏览: 358
水库调度问题可以使用遗传算法进行求解。以下是一个简单的遗传算法求解水库调度问题的Python代码:
```python
import random
# 定义水库调度问题的目标函数
def objective_function(x):
# x是一个长度为24的列表,表示24小时内每个时段的水位调度方案
# 计算水库的出水量和尾水位
outflow = [0] * 24
water_level = [0] * 24
water_level[0] = 20 # 初始水位为20米
for i in range(1, 24):
outflow[i] = min(x[i], 1000 * (water_level[i - 1] - 15))
water_level[i] = water_level[i - 1] + 0.5 * (x[i] - outflow[i])
# 计算目标函数值
obj_value = 0
for i in range(24):
obj_value += 10 * (water_level[i] - 15) ** 2 + outflow[i] ** 2
return obj_value
# 定义遗传算法的相关参数
population_size = 50 # 种群大小
chromosome_length = 24 # 染色体长度
mutation_probability = 0.01 # 变异概率
crossover_probability = 0.6 # 交叉概率
max_generation = 100 # 最大迭代次数
# 初始化种群
population = []
for i in range(population_size):
chromosome = [random.randint(0, 100) for j in range(chromosome_length)]
population.append(chromosome)
# 开始遗传算法的迭代过程
for generation in range(max_generation):
# 评估种群中每个染色体的适应度
fitness_values = [1 / objective_function(chromosome) for chromosome in population]
# 找出当前种群中最优秀的染色体
best_chromosome = population[fitness_values.index(max(fitness_values))]
# 输出当前迭代次数和最优解
print("Generation:", generation, "Best solution:", best_chromosome, "Objective function value:", objective_function(best_chromosome))
# 生成新的种群
new_population = []
while len(new_population) < population_size:
# 选择父代染色体
parent1 = population[roulette_wheel_selection(fitness_values)]
parent2 = population[roulette_wheel_selection(fitness_values)]
# 交叉产生子代染色体
if random.random() < crossover_probability:
offspring1, offspring2 = crossover(parent1, parent2)
else:
offspring1, offspring2 = parent1, parent2
# 变异产生新的染色体
if random.random() < mutation_probability:
offspring1 = mutation(offspring1)
if random.random() < mutation_probability:
offspring2 = mutation(offspring2)
# 将新的染色体加入新的种群中
new_population.append(offspring1)
new_population.append(offspring2)
population = new_population
# 定义选择操作(轮盘赌选择)
def roulette_wheel_selection(fitness_values):
total_fitness = sum(fitness_values)
selection_probabilities = [fitness_value / total_fitness for fitness_value in fitness_values]
cum_probabilities = [sum(selection_probabilities[:i+1]) for i in range(len(selection_probabilities))]
random_value = random.random()
for i in range(len(cum_probabilities)):
if random_value <= cum_probabilities[i]:
return i
# 定义交叉操作(单点交叉)
def crossover(parent1, parent2):
crossover_point = random.randint(1, chromosome_length - 1)
offspring1 = parent1[:crossover_point] + parent2[crossover_point:]
offspring2 = parent2[:crossover_point] + parent1[crossover_point:]
return offspring1, offspring2
# 定义变异操作(随机重置)
def mutation(chromosome):
mutated_chromosome = chromosome.copy()
mutation_point = random.randint(0, chromosome_length - 1)
mutated_chromosome[mutation_point] = random.randint(0, 100)
return mutated_chromosome
```
在上面的代码中,目标函数是根据24小时内的水位调度方案计算水库的出水量和尾水位,并计算目标函数值。遗传算法的迭代过程包括种群初始化、评估适应度、选择、交叉、变异等操作。其中选择操作采用轮盘赌选择,交叉操作采用单点交叉,变异操作采用随机重置。最终输出的是迭代过程中每一代的最优解和目标函数值。
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