Find Items & Indices In A List...

[Joachim Bauch]

Hi Andrea,

andrea.gavana at agip.it wrote:
>       I was wondering if there is a faster/nicer method (than a for loop)
> that will allow me to find the elements (AND their indices) in a list that
> verify a certain condition. For example, assuming that I have a list like:
> 
> mylist = [0, 1, 1, 1, 1, 5, 6, 7, 8, 1, 10]
> 
> I would like to find the indices of the elements in the list that are equal
> to 1 (in this case, the 1,2,3,4,9 elements are equal to 1). I could easily
> use a for loop but I was wondering if there is a faster method...

you could use something like this:

 >>> mylist = [0, 1, 1, 1, 1, 5, 6, 7, 8, 1, 10]
 >>> [x[0] for x in enumerate(mylist) if x[1] == 1]
[1, 2, 3, 4, 9]

Greetings,
   Joachim

-- 
Joachim Bauch, struktur AG
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