Python string count not working properly?

Question

There are two occurrences of 'aba' in 'ababa' (0th index and 2nd index):

myString = 'ababa'
print(myString.count('aba'))

Yet this code outputs a value of: 1
I know this issue seems really simple, but shouldn't the answer be 2 here?
If not, then isn't the count function not really doing what it's supposed to?

Is there a simple alternative?

It is correct. `ababa` - `aba` = `ba`. `ba` is not `aba`. So thats 1. — Moon Cheesez, Jun 23 '16 at 01:32
There's also this: http://stackoverflow.com/questions/2970520/string-count-with-overlapping-occurrences — Headcrab, Jun 23 '16 at 01:35
if you did `"a".count("a")` would you expect infinity as the count? Why not? — TessellatingHeckler, Jun 23 '16 at 01:41

score 10 · Accepted Answer · edited Jun 23 '16 at 01:41

From the Python string function documentation

Return the number of non-overlapping occurrences of substring sub in the range [start, end]. Optional arguments start and end are interpreted as in slice notation.

count does not count overlapping occurrences.

If you want to count overlapping occurrences you can use regex with a lookahead assertion:

import re
print(len(re.findall('(?=aba)', 'ababa')))

score 2 · Answer 2 · answered Jun 23 '16 at 01:34

Documentation to the rescue: https://docs.python.org/2/library/string.html

Return the number of (non-overlapping) occurrences of substring sub in string s[start:end]. Defaults for start and end and interpretation of negative values are the same as for slices.

Python string count not working properly?

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