find all index positions

Tim Chase python.list at tim.thechases.com
Thu May 11 11:58:12 EDT 2006


> say i have string like this
> astring = 'abcd efgd 1234 fsdf gfds abcde 1234'
> if i want to find which postion is 1234, how can i
> achieve this...? i want to use index() but it only give
> me the first occurence. I want to know the positions of
> both "1234"

Well, I'm not sure how efficient it is, but the following 
seemed to do it for me:

 >>> a = 'abcd efgd 1234 fsdf gfds abcde 1234'
 >>> thing = '1234'
 >>> offsets = [i for i in range(len(a)) if 
a.startswith(thing, i)]
 >>> print offsets
[10, 31]


HTH,

-tkc







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