CODEWITHSUNDEEP
pythonfilecountcomparison
mrpopo
mrpopo

Reputation: 1563

How to count how many lines in a file are the same?

I have a text document in the format of:

-1+1
-1-1
+1+1
-1-1
+1-1
...

I want to have a program that counts how many lines have -1+1 lines and +1-1 lines. The program would then just need to return the value of how many lines are like this.

I have written the code:

f1 = open("results.txt", "r")
fileOne = f1.readlines()
f1.close()

x = 0
for i in fileOne:
    if i == '-1+1':
        x += 1
    elif i == '+1-1':
        x += 1
    else:
        continue

print x

But for some reason, it always returns 0 and I have no idea why.

Upvotes: 6

Views: 10045

Answers (3)

Rich Tier
Rich Tier

Reputation: 9441

If you don't want to import a module, enjoy short code, and like a bit of 'list' comprehension :

with open('results.txt') as infile:
    counts = { key: infile.count(key) for key in ['-1+1', '+1-1'] }

Then of course access counts as a dict

Upvotes: 0

Martijn Pieters
Martijn Pieters

Reputation: 1122042

Use collections.Counter instead:

import collections

with open('results.txt') as infile:
    counts = collections.Counter(l.strip() for l in infile)
for line, count in counts.most_common():
    print line, count

Most of all, remove whitespace (the newline specifically, but any other spaces or tabs might interfere too) when counting your lines.

Upvotes: 19

eumiro
eumiro

Reputation: 212885

The .readlines() leaves the \n in the lines, that's why they don't match.

Upvotes: 8

Related Questions