用粒子群算法解决投资组合优化问题,用python,请提供源代码和数据,代码一定要可运行
时间: 2024-02-24 18:57:11 浏览: 61
基于Python实现的使用粒子群优化算法求解旅行商问题.zip
好的,下面是用粒子群算法解决投资组合优化问题的 Python 代码和数据。
数据可以使用随机生成的数据,例如:
```python
import numpy as np
# 生成随机的收益率和方差
np.random.seed(42)
n = 10
mu = np.random.rand(n)
sigma = np.random.rand(n, n)
sigma = np.dot(sigma, sigma.T) # 保证方差协方差矩阵为正定矩阵
```
代码:
```python
import numpy as np
def objective_function(x, mu, sigma):
# 计算投资组合的收益率和方差
r = np.dot(mu, x)
v = np.dot(x, np.dot(sigma, x))
return r, v
def particle_swarm_optimization(obj_func, n_particles, n_iterations, bounds):
# 粒子群算法
# obj_func: 目标函数
# n_particles: 粒子数
# n_iterations: 迭代次数
# bounds: 变量的取值范围
# 初始化粒子群
particles = np.random.rand(n_particles, len(bounds)) * (bounds[:, 1] - bounds[:, 0]) + bounds[:, 0]
velocities = np.zeros_like(particles)
p_best = particles.copy()
p_best_scores = np.zeros(n_particles)
for i in range(n_particles):
p_best_scores[i] = obj_func(p_best[i])[0]
g_best = p_best[p_best_scores.argmin()].copy()
# 开始迭代
for i in range(n_iterations):
for j in range(n_particles):
# 更新速度和位置
r1, r2 = np.random.rand(2, len(bounds))
velocities[j] = velocities[j] + r1 * (p_best[j] - particles[j]) + r2 * (g_best - particles[j])
particles[j] = particles[j] + velocities[j]
# 边界处理
particles[j] = np.maximum(particles[j], bounds[:, 0])
particles[j] = np.minimum(particles[j], bounds[:, 1])
# 更新个体最优和全局最优
score = obj_func(particles[j])[0]
if score < p_best_scores[j]:
p_best[j] = particles[j].copy()
p_best_scores[j] = score
if score < obj_func(g_best)[0]:
g_best = particles[j].copy()
return g_best
# 测试代码
np.random.seed(42)
n = 10
mu = np.random.rand(n)
sigma = np.random.rand(n, n)
sigma = np.dot(sigma, sigma.T)
bounds = np.ones((n, 2)) * np.array([0, 1]) # 变量的取值范围为 [0, 1]
x_best = particle_swarm_optimization(lambda x: objective_function(x, mu, sigma), 100, 100, bounds)
print(x_best)
print(objective_function(x_best, mu, sigma))
```
注意:由于粒子群算法是随机的,所以每次运行结果可能会有所不同。
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