机器学习对文本的聚类KMeans

使用kmeans进行文本的聚类

from __future__ import print_function

import time

from sklearn.feature_extraction.text import TfidfVectorizer
import matplotlib.pyplot as plt
from sklearn.cluster import KMeans, MiniBatchKMeans
import pymssql


#读取sqlserver数据库
def get_dbdata():
conn_read = pymssql.connect("127.0.0.1", "sa", "###", "test", charset="GBK")
dataset = []
sql = "select guanjianci from julei_test"
cursor = conn_read.cursor()
cursor.execute(sql)
data_count = 0
for line in cursor:
data_count +=1
dataset.append(line[0])
cursor.close()
conn_read.close()
print(dataset)
return dataset

def transform(dataset, n_features=1000):
vectorizer = TfidfVectorizer(max_df=0.5, max_features=n_features, min_df=2, use_idf=True)
X = vectorizer.fit_transform(dataset)
return X, vectorizer


def train(X, vectorizer, true_k=10, minibatch=False, showLable=False):
# 使用采样数据还是原始数据训练k-means，
if minibatch:
km = MiniBatchKMeans(n_clusters=true_k, init='k-means++', n_init=1,
init_size=1000, batch_size=1000, verbose=False)
else:
km = KMeans(n_clusters=true_k, init='k-means++', max_iter=300, n_init=1,
verbose=False)
km.fit(X)
if showLable:
print("Top terms per cluster:")
order_centroids = km.cluster_centers_.argsort()[:, ::-1]
terms = vectorizer.get_feature_names()
print(vectorizer.get_stop_words())
for i in range(true_k):
print("Cluster %d:" % i, end='')
for ind in order_centroids[i, :10]:
print(' %s' % terms[ind], end='')
print()
result = list(km.predict(X))
print('Cluster distribution:')
print(dict([(i, result.count(i)) for i in result]))
return -km.score(X)

#指定簇的个数k
def k_determin():
'''测试选择最优参数'''
dataset = get_dbdata()
print("%d documents" % len(dataset))
X, vectorizer = transform(dataset, n_features=500)
true_ks = []
scores = []
#中心点的个数从3到200(根据自己的数据量改写)
for i in range(3, 200, 1):
score = train(X, vectorizer, true_k=i) / len(dataset)
print(i, score)
true_ks.append(i)
scores.append(score)
plt.figure(figsize=(8, 4))
plt.plot(true_ks, scores, label="error", color="red", linewidth=1)
plt.xlabel("n_features")
plt.ylabel("error")
plt.legend()
plt.show()


def main():
'''在最优参数下输出聚类结果'''
dataset = get_dbdata()
X, vectorizer = transform(dataset, n_features=500)
score = train(X, vectorizer, true_k=25, showLable=True) / len(dataset)
print(score)

if __name__ == '__main__':
start=time.time()
#k_determin()#先确定k值
main()
end=time.time()
print('程序运行时间',end-start)