用python画出爬山者的适合度与世代数的关系。
时间: 2023-06-10 21:06:33 浏览: 145
好的,我来给你演示一下如何用 Python 画出爬山者的适合度与世代数的关系。
首先,我们需要一个适合度函数,这里我们采用标准的 Rastrigin 函数:
```python
import math
def rastrigin(x, A=10):
n = len(x)
sum = A*n
for i in range(n):
sum += x[i]**2 - A*math.cos(2*math.pi*x[i])
return sum
```
接下来,我们需要一个爬山算法来求解最优解,这里我们采用基本的随机爬山算法:
```python
import random
def random_hill_climbing(f, bounds, max_iter=1000):
best_fitness = float('inf')
best_solution = None
for i in range(max_iter):
solution = [random.uniform(bounds[j][0], bounds[j][1]) for j in range(len(bounds))]
fitness = f(solution)
if fitness < best_fitness:
best_fitness = fitness
best_solution = solution
return best_fitness, best_solution
```
最后,我们可以用 Matplotlib 库来画出适合度与世代数的关系图:
```python
import matplotlib.pyplot as plt
bounds = [(-5.12, 5.12)]*10
num_generations = 50
fitness_history = []
for i in range(num_generations):
fitness, _ = random_hill_climbing(rastrigin, bounds)
fitness_history.append(fitness)
plt.plot(range(num_generations), fitness_history)
plt.xlabel('Generation')
plt.ylabel('Fitness')
plt.title('Fitness vs. Generation')
plt.show()
```
运行这段代码,我们就可以得到爬山者的适合度与世代数的关系图了。
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