Python3 - For loop access array value

Question

I have below Python script, counts the number of words in a text file:

from collections import Counter

def main():
    with open(TEXT_FILE) as f:
        wordscounts = Counter(f.read().split())
        print(wordscounts)

Above gives me:

Counter({'invoice': 10, 'USD': 8, 'order': 5})

Now I want to add these words to another text file dictionary.txt, like:

invoice 10
USD 8
order 5

And next time I process a file, and check for word frequency, for example:

 Counter({'invoice': 2, 'USD': 1, 'tracking': 3})

It should add the count to the words already in the file, and append the new.

So dictionary.txt becomes:

invoice 12
USD 9
order 5
tracking 3

If I try to iterate through the wordscount, I only get the actual word:

 for index, wordcount in enumerate(wordscounts):
     print(wordcount)

gives me:

invoice
USD
order

But not the word count.

There are some missing steps that make it not clear what you mean by wordscounts - for example, is it a Counter object? if so then you are iterating through the object incorrectly. Also, if you are iterating a dictionary then you are also incorrectly looping. — Chinny84
– Chinny84, Commented May 7, 2019 at 11:44
I have added from collections import Counter to my quesiton. Can you elaborate on why I am looping incorrectly? — oliverbj
– oliverbj, Commented May 7, 2019 at 11:45
I see that you did clarify what the wordscounts was. But, the enumerate wordscounts does not give you the values for the counters. It is the same principle of looping a dict for keys and values. The answer below shows how one can do it. — Chinny84
– Chinny84, Commented May 7, 2019 at 11:46
A Counter is a dict subclass so you can use dictionary methods like for word, wordcount in wordscounts.items(): — Andrew Allen
– Andrew Allen, Commented May 7, 2019 at 11:46
You may want to look at stackoverflow.com/questions/28153549/… — Sparky05
– Sparky05, Commented May 7, 2019 at 11:59

Sparky05 · Accepted Answer · 2019-05-07 13:14:22Z

2

You need to read the Counter dictionary. Small example

from collections import Counter
wordcount_1 = Counter("an example test test test".split())
wordcount_2 = Counter("another example test".split())

for word in wordcount_1:
    print(word, wordcount_1[word])
# example 1
# test 3
# an 1

If you want to build the sum (in memory) (as mentioned here), use

total = sum([wordcount_1, word_count_2], Counter())

edited May 7, 2019 at 13:14

answered May 7, 2019 at 11:45

Sparky05

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4 Comments

oliverbj Over a year ago

Ah, this works perfectly! Do you have any idea regarding the last part of my question? Adding the words to another file - but only updating the word count if the word already exists.

Sparky05 Over a year ago

If possible, have the full word counter in memory and save afterwards. If that's not possible because of the size of your problem, I would sort the save by the words, which will fasten your search (and check if something is new).

oliverbj Over a year ago

Would you mind giving a simple example of this? I am brand new to Python, so still learning.

Sparky05 Over a year ago

Added the easier in memory variant, which I would try first

ruhhh · Accepted Answer · 2019-05-10 05:07:37Z

1

You can get the actual wordcount using:

for index, wordcount in enumerate(wordscounts):
     print(wordscounts[wordcount])

Printing wordcount only gives you the key, while printing wordcounts[wordcount] gives you the value.

edited May 10, 2019 at 5:07

answered May 7, 2019 at 11:44

ruhhh

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