Let's say my text file consists of the following text:
The quick brown fox jumped over the lazy dogs. A stitch in time saves nine. The quick brown stitch jumped over the lazy time. The fox in time saves a dog.
I want to use sk-learn's CountVectorizer to get a word count for all words in the file. (I know there are other ways to do this, but I want to use CountVectorizer for a few reasons.) This is my code:
from nltk.corpus import stopwords
from sklearn.feature_extraction.text import CountVectorizer
text = input('Please enter the filepath for the text: ')
text = open(text, 'r', encoding = 'utf-8')
tokens = CountVectorizer(analyzer = 'word', stop_words = 'english')
X = tokens.fit_transform(text)
dictionary = tokens.vocabulary_
Except that when I call dictionary
, it gives me the wrong counts:
>>> dictionary
{'time': 9, 'dog': 1, 'stitch': 8, 'quick': 6, 'lazy': 5, 'brown': 0, 'saves': 7, 'jumped': 4, 'fox': 3, 'dogs': 2}
Can anyone advise on the (doubtless obvious) mistake I'm making here?
vocabulary_
is a dict/mapping of the terms to their indices in the document-term matrix, not the counts:
vocabulary_
: A mapping of terms to feature indices.
X
is what actually gives you the matrix of feature indices and corresponding counts.
>>> for i in X:
... print(i)
...
(0, 1) 1
(0, 7) 2
(0, 9) 3
(0, 8) 2
(0, 2) 1
(0, 5) 2
(0, 4) 2
(0, 3) 2
(0, 0) 2
(0, 6) 2
e.g. 9 -> 'time'
has a count of 3.