list.index() like...but returning lists (for avoiding '0' on multiples hits)

[Dang Griffith]

On Mon, 22 Dec 2003 17:37:46 -0300, Gerardo Herzig -Departamento de
Proyectos Especiales e Internet- Facultad de Medicina
<gherzig at fmed.uba.ar> wrote:

>Hi....i asume this is a veeeery usual question. I'm searching on python.org, 
>but their results is not giving me the answer that i looking for...So, here i 
>go...when i have myList = [2,4,2,0] ...myList.index(2) returns 0 (python 
>2.2)....There is a built-in function-method that returns [0,2]? 
>
>Well, sory if RTFM is the answer!!
    Do you mean a function that returns a list of the indices of all
occurrences of the specified value?   I don't think there's a builtin,
but you could do something like this:

def indices(lst, val):
    """ Return a list of indices of matches. """
    return [i for i in range(0, len(lst)) if lst[i] == val]

myList = [2, 4, 2, 0]
print indices(myList, 2)
# [0, 2]

    --dang