Python抽出テキストtf,idf
1722 ワード
"""python tfidf """
import math
from collections import Counter
# 1.
corpus = [
'this is the first document',
'this is the second second document',
'and the third one',
'is this the first document'
]
# 2.
word_list = []
for i in range(len(corpus)):
word_list.append(corpus[i].split(' '))
print('2-->', word_list)
# 3.
countlist = []
for i in range(len(word_list)):
count = Counter(word_list[i])
countlist.append(count)
print('3 -->', countlist)
# 4. tfidf
# count[word] , sum(count.values())
def tf(word, count):
return count[word] / sum(count.values())
#
def n_containing(word, count_list):
return sum(1 for count in count_list if word in count)
# len(count_list) ,n_containing(word, count_list) , 1 0
def idf(word, count_list):
return math.log(len(count_list) / (1 + n_containing(word, count_list)))
# tf idf
def tfidf(word, count, count_list):
return tf(word, count) * idf(word, count_list)
all_dict = {}
for counte in countlist:
counter = dict(counte)
for k, v in counter.items():
try:
all_dict[k] += v
except:
all_dict[k] = v
print('merge-->', all_dict)
with open('tf.txt', 'w+') as tfin, open('idf.txt', 'w+') as idfin:
for k in all_dict.keys():
# k_tf = tf(k, all_dict)
tfin.write(k + ' ' + str(all_dict[k]) + '
')
k_idf = idf(k, countlist)
idfin.write(k + ' ' + str(k_idf) + '
')