import nltk
import random
from nltk.corpus import movie_reviews
documents=[(list(movie_reviews.words(fileid)),category)
for category in movie_reviews.categories()
for fileid in movie_reviews.fileids(category)]
random.shuffle(documents)
#print(documents[1])
all_words=[]
for w in movie_reviews.words():
all_words.append(w.lower())
all_words=nltk.FreqDist(all_words)
word_features = list(all_words.keys())[:3000]
def find_features(document):
words = set(document)
features=[]
for w in word_features:
features[w]= (w in words)
return features
print((find_features(movie_reviews.words('neg/cv000_29416.txt'))))
featuresets = [(find_features(rev), category) for (rev,category) in documents]
After run, I am getting the error
features[w]= (w in words)
TypeError: list indices must be integers, not str
Please help me to solve it...
Only change that needs to be made is that features
must be initialized to a dict
({}
) rather than a list
([]
) and then you could populate it's contents.
The TypeError
was because word_features
is a list of strings which you were trying to index using a list and lists can't have string indices.
features={}
for w in word_features:
features[w] = (w in words)
Here, the elements present in word_features
constitute the keys
of dictionary, features
holding boolean values, True
based on whether the same element appears in words
(which holds unique items due to calling of set()
) and False
for the vice-versa situation.