Extract words surrounding a search word

python regex find text-processing
PepperoniPizza picture PepperoniPizza · Jul 15, 2013 · Viewed 9.8k times · Source

I have this script that does a word search in text. The search goes pretty good and results work as expected. What I'm trying to achieve is extract n words close to the match. For example:

The world is a small place, we should try to take care of it.

Suppose I'm looking for place and I need to extract the 3 words on the right and the 3 words on the left. In this case they would be:

left -> [is, a, small]
right -> [we, should, try]

What is the best approach to do this?

Thanks!

Answer

HennyH picture HennyH · Jul 15, 2013 
def search(text,n):
    '''Searches for text, and retrieves n words either side of the text, which are retuned seperatly'''
    word = r"\W*([\w]+)"
    groups = re.search(r'{}\W*{}{}'.format(word*n,'place',word*n), text).groups()
    return groups[:n],groups[n:]

This allows you to specify how many words either side you want to capture. It works by constructing the regular expression dynamically. With 

t = "The world is a small place, we should try to take care of it."
search(t,3)
(('is', 'a', 'small'), ('we', 'should', 'try'))

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