from sklearn.feature_extraction.text import CountVectorizer
vectorizer = CountVectorizer()
vectorizer = vectorizer.fit(word_data)
freq_term_mat = vectorizer.transform(word_data)
from sklearn.feature_extraction.text import TfidfTransformer
tfidf = TfidfTransformer(norm="l2")
tfidf = tfidf.fit(freq_term_mat)
Ttf_idf_matrix = tfidf.transform(freq_term_mat)
voc_words = Ttf_idf_matrix.getfeature_names()
print "The num of words = ",len(voc_words)
当我运行包含这段代码的程序时，出现以下错误：
回溯（最近一次调用）：文件“vectorize_text.py”，第 87 行，在
voc_words = Ttf_idf_matrix.getfeature_names()
文件“/home/farheen/anaconda/lib/python2.7/site->packages/scipy/sparse/ base.py", line 499, in getattr
raise AttributeError(attr + " not found")
AttributeError: get_feature_names not found
请建议我一个解决方案。