How to find how many times a word appears in a array? Python

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item frequency count in python

Quick question

How do you find how many times a word appears in an array?

I have an array that has around 5000 words of text, and i want to find how many times the word "help" appears in the array. How do i do this?

the array is stored in x, so my code looks like this:

x = [...]
word = "help"

and then i dont know what to put to get the number of times "help" appears in x

thank you for any help!

What have you tried so far? Can you show us the code you have up to now so that we can help you better. — Levon, May 04 '12 at 05:46
I havent tried any code because i dont know how i would do it. — Hoops, May 04 '12 at 05:48
See the answer given here http://stackoverflow.com/questions/893417/item-frequency-count-in-python — RedBaron, May 04 '12 at 05:51
In addition, if you actually have it as a list instead of a string, you can turn it into a string with "".join(MyArray) — Josiah, May 04 '12 at 05:54
Added [tag:homework] to the post (can't imagine it to be anything else). — georg, May 04 '12 at 06:57

score 6 · Answer 1 · answered May 04 '12 at 05:48

6

>>> import collections
>>> print collections.Counter(['a', 'word', 'is', 'a', 'thing', 'that', 'is', 'countable'])
Counter({'a': 2, 'is': 2, 'word': 1, 'that': 1, 'countable': 1, 'thing': 1})

This is 2.7+, a Counter.

Based on your edit, where each element in the list is a letter instead of the full word, then:

>>> import re
>>> letters = 
['i', 'n', 'e', 'e', 'd', 's', 'o', 'm', 'e', 'h', 'e', 'l', 'p', 'h', 'e', 'l', 'p', 'm', 'e', 'p', 'l', 'e', 'a', 's', 'e', 'I', 'n', 'e', 'e', 'd', 'h', 'e', 'l', 'p']
>>> len(re.findall('help', "".join(letters)))
3

answered May 04 '12 at 05:48

sberry

113,858
17
127
157

+1 for the cleanest and most powerful solution. That still doesn't help him a lot, if this was a homework question and he was meant to do it manually. :-) – Has QUIT--Anony-Mousse May 04 '12 at 05:53
I didn't assume it to be homework, as the tag was not included. But, point taken. – sberry May 04 '12 at 05:57

Abhijit · Answer 2 · 2012-05-04T08:25:24.747

As @sberry has depicted, Counter would server the purpose, but in case you are only searching a single word once and not interested to get the occurrence of all the words, you can use a simpler tool for the purpose

(I have taken the example from sberry)

Given a list of words to find the occurrence of any given words, you can use the count method of the list

>>> list_of_words=['a', 'word', 'is', 'a', 'thing', 'that', 'is', 'countable']
>>> list_of_words.count('is')
2

As your comments have shown you may be interested to search on a list of characters. Such as

letters =
['i', 'n', 'e', 'e', 'd', 's', 'o', 'm', 'e', 'h', 'e', 'l', 'p', 'h', 'e', 'l', 'p', 'm', 'e', 'p', 'l', 'e', 'a', 's', 'e', 'I', 'n', 'e', 'e', 'd', 'h', 'e', 'l', 'p']

You can also use the count on the string after is generated by concatenating all the characters

>>> ''.join(letters).count('help')
3

In case the words are jumbled, collections.Counter ad do magic here

>>> def count_words_in_jumbled(jumbled,word):
    jumbled_counter = collections.Counter(jumbled)
    word_counter = collections.Counter(word)
    return min(v /word_counter[k] for k,v in jumbled_counter.iteritems() if k in word)

>>> count_words_in_jumbled(['h','e','l','l','h','e','l','l','h','e','l'],'hel')
3
>>> count_words_in_jumbled(['h','e','l','l','h','e','l','l','h','e','l'],'hell')
2
>>> count_words_in_jumbled(['h','x','e','y','l','u','p'] ,'help')
1

-1 @Abhijit the join() method will not work if the array is like `['h','x','e','y','l','u','p']` — Ashwini Chaudhary, May 04 '12 at 07:59
@AshwiniChaudhary: OP never mentioned that the letters are jumbled. I have also read through the comments but not a pinch of hint indicating the same. — Abhijit, May 04 '12 at 08:03
it looks like you're correct, can't do a +1 my vote is locked until you edit the solution. — Ashwini Chaudhary, May 04 '12 at 08:09
@AshwiniChaudhary: I have edited my answer. Check the last part of it :-) — Abhijit, May 04 '12 at 08:25

score 0 · Answer 3 · answered May 04 '12 at 07:12

0

nhelps = len(''.join(charlist).split('help')[1:]

answered May 04 '12 at 07:12

justnpoole.

1

How to find how many times a word appears in a array? Python

3 Answers3