举例一个问题经过python编程来实现FCM算法
时间: 2023-06-17 18:05:58 浏览: 110
FCM算法简单实现python
FCM(模糊C均值)算法是一种聚类算法,用于将一组数据分成多个簇。下面是一个使用Python实现FCM算法的示例:
``` python
import numpy as np
import random
class FCM:
def __init__(self, n_clusters=2, max_iter=100, m=2, error=1e-5):
self.u = None
self.centers = None
self.n_clusters = n_clusters
self.max_iter = max_iter
self.m = m
self.error = error
def fit(self, X):
n_samples = X.shape[0]
c = self.n_clusters
u = np.random.rand(n_samples, c)
u = u / np.sum(u, axis=1)[:, np.newaxis] # 归一化
centers = np.zeros((c, X.shape[1]))
iter_num = 0
while iter_num < self.max_iter:
u2 = u ** self.m
centers = np.dot(u2.T, X) / np.sum(u2, axis=0)[:, np.newaxis]
d = np.zeros((n_samples, c))
for j in range(c):
diff = X - centers[j, :]
d[:, j] = np.sum(diff * diff, axis=1)
u_old = u
u = 1 / d ** (1 / (self.m - 1))
u = u / np.sum(u, axis=1)[:, np.newaxis]
if np.max(np.abs(u - u_old)) < self.error:
break
iter_num += 1
self.u = u
self.centers = centers
return centers
if __name__ == '__main__':
X = np.random.rand(100, 2) # 生成随机数据
fcm = FCM(n_clusters=3)
centers = fcm.fit(X)
print(centers)
```
在上面的代码中,我们首先定义了一个FCM类,该类有一些参数,包括簇的数量、最大迭代次数、模糊参数和误差。然后,我们使用随机数生成器生成一些随机数据,并使用我们的FCM类对数据进行聚类。
在fit()方法中,我们首先初始化隶属度矩阵。然后使用循环迭代来更新隶属度和簇心,直到达到最大迭代次数或达到足够小的误差。最后返回簇心。
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