如何使用word2vec进行文本分类

时间:2018-04-04 06:10:35

标签: python-3.x word2vec gensim text-classification

我想使用word2vec执行文本分类。 我有文字的向量。

ls = []
sentences = lines.split(".")
for i in sentences:
    ls.append(i.split())
model = Word2Vec(ls, min_count=1, size = 4)
words = list(model.wv.vocab)
print(words)
vectors = []
for word in words:
    vectors.append(model[word].tolist())
data = np.array(vectors)
data

输出:

array([[ 0.00933912,  0.07960335, -0.04559333,  0.10600036],
       [ 0.10576613,  0.07267512, -0.10718666, -0.00804013],
       [ 0.09459028, -0.09901826, -0.07074171, -0.12022413],
       [-0.09893986,  0.01500741, -0.04796079, -0.04447284],
       [ 0.04403428, -0.07966098, -0.06460238, -0.07369237],
       [ 0.09352681, -0.03864434, -0.01743148,  0.11251986],.....])

我如何进行分类(产品和非产品)?

1 个答案:

答案 0 :(得分:3)

您已经使用model.wv.syn0获得了单词向量数组。如果打印出来,则可以看到一个数组,其中包含单词的每个对应向量。

您可以在此处使用 Python3 查看示例:

import pandas as pd
import os
import gensim
import nltk as nl
from sklearn.linear_model import LogisticRegression


#Reading a csv file with text data
dbFilepandas = pd.read_csv('machine learning\\Python\\dbSubset.csv').apply(lambda x: x.astype(str).str.lower())

train = []
#getting only the first 4 columns of the file 
for sentences in dbFilepandas[dbFilepandas.columns[0:4]].values:
    train.extend(sentences)

# Create an array of tokens using nltk
tokens = [nl.word_tokenize(sentences) for sentences in train]

现在是使用向量模型的时候了,在此示例中,我们将计算LogisticRegression。

model = gensim.models.Word2Vec(tokens, size=300, min_count=1, workers=4)
print("\n Training the word2vec model...\n")
# reducing the epochs will decrease the computation time
model.train(tokens, total_examples=len(tokens), epochs=4000)
# You can save your model if you want....

# The two datasets must be the same size
max_dataset_size = len(model.wv.syn0)

Y_dataset = []
# get the last number of each file. In this case is the department number
# this will be the 0 or 1, or another kind of classification. ( to use words you need to extract them differently, this way is to numbers)
with open("dbSubset.csv", "r") as f:
    for line in f:
        lastchar = line.strip()[-1]
        if lastchar.isdigit():
            result = int(lastchar) 
            Y_dataset.append(result) 
        else:
            result = 40 


clf = LogisticRegression(random_state=0, solver='lbfgs', multi_class='multinomial').fit(model.wv.syn0, Y_dataset[:max_dataset_size])

# Prediction of the first 15 samples of all features
predict = clf.predict(model.wv.syn0[:15, :])
# Calculating the score of the predictions
score = clf.score(model.wv.syn0, Y_dataset[:max_dataset_size])
print("\nPrediction word2vec : \n", predict)
print("Score word2vec : \n", score)

您还可以计算属于您创建的模型词典的单词的相似度:

print("\n\nSimilarity value : ",model.wv.similarity('women','men'))

您可以找到更多使用here的功能。