Finding values on sequences and .index()
Donald O'Donnell
donod at home.com
Wed Dec 6 22:33:58 EST 2000
rhamorim at my-deja.com wrote:
>
> Hi.
>
> I have a list that may have many ocurrences of the same data. How do I
> find the indexes for all ocurrences of it? list.index(value) only works
> for the first ocurrence.
...
How about using a list comprehension (ver 2.0) like this:
>>> a = [1, 2, 3, 4, 1, 5, 6, 7, 1, 8, 9, 1]
>>> n = 1
>>> x = [i for i in range(len(a)) if a[i]==n]
>>> x
[0, 4, 8, 11]
Or doing it the old fashioned way (ver 1.5):
>>> x = []
>>> for i in range(len(a)):
... if a[i] == n: x.append(i)
...
>>> x
[0, 4, 8, 11]
Hope this helps.
Don
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