你写一个使用余弦相似度作为距离度量的Kmeans算法
时间: 2024-02-22 08:57:10 浏览: 166
余弦相似度算法实现
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好的,我可以为您提供一个使用余弦相似度作为距离度量的Kmeans算法的Python代码,示例如下:
```python
import numpy as np
from sklearn.metrics.pairwise import cosine_similarity
class CosineKmeans:
def __init__(self, n_clusters=8, max_iter=300, random_state=None):
self.n_clusters = n_clusters
self.max_iter = max_iter
self.random_state = random_state
def fit(self, X):
rng = np.random.RandomState(self.random_state)
n_samples, n_features = X.shape
# Initialize centroids
centroids_indices = rng.permutation(n_samples)[:self.n_clusters]
self.centroids = X[centroids_indices]
for i in range(self.max_iter):
# Calculate cosine similarities between each sample and each centroid
similarities = cosine_similarity(X, self.centroids)
# Assign each sample to the closest centroid
labels = np.argmax(similarities, axis=1)
# Update centroids
for j in range(self.n_clusters):
mask = labels == j
if np.sum(mask) > 0:
self.centroids[j] = np.mean(X[mask], axis=0)
def predict(self, X):
similarities = cosine_similarity(X, self.centroids)
labels = np.argmax(similarities, axis=1)
return labels
```
在这个示例中,我们使用了sklearn中的cosine_similarity函数来计算余弦相似度,fit方法用于训练模型,predict方法用于预测样本所属的簇。您可以根据自己的需求修改代码并进行测试。
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