Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
366 views
in Technique[技术] by (71.8m points)

string - n-grams in python, four, five, six grams?

I'm looking for a way to split a text into n-grams. Normally I would do something like:

import nltk
from nltk import bigrams
string = "I really like python, it's pretty awesome."
string_bigrams = bigrams(string)
print string_bigrams

I am aware that nltk only offers bigrams and trigrams, but is there a way to split my text in four-grams, five-grams or even hundred-grams?

Thanks!

Question&Answers:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

Great native python based answers given by other users. But here's the nltk approach (just in case, the OP gets penalized for reinventing what's already existing in the nltk library).

There is an ngram module that people seldom use in nltk. It's not because it's hard to read ngrams, but training a model base on ngrams where n > 3 will result in much data sparsity.

from nltk import ngrams

sentence = 'this is a foo bar sentences and i want to ngramize it'

n = 6
sixgrams = ngrams(sentence.split(), n)

for grams in sixgrams:
  print grams

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

1.4m articles

1.4m replys

5 comments

57.0k users

...