index in "double" list

[Boštjan Jerko]

Hello!

I have a list of lists (e.g. [[1,"a"],[2,"b"],[3,"c"]]) and
would like to do index on the first element of the lists.
Can it be done?

B.

[Larry Bates]

Re: index in "double&qu ot; list

If you have list:

t=[[1,"a"],[2,"b"],[3,"c"]]

The first element of each list contained
in t is accessed by:

t[n][0]

where n is the element number you wish to access
(zero based of course).

-Larry

"Boštjan Jerko" <bostjan.jerko@ mf.uni-lj.si> wrote in message
news:mailman.11 54.1075795507.1 2720.python-list@python.org ...[color=blue]
> Hello!
>
> I have a list of lists (e.g. [[1,"a"],[2,"b"],[3,"c"]]) and
> would like to do index on the first element of the lists.
> Can it be done?
>
> B.
>[/color]

[Dan Bishop]

Re: index in &quot;double&qu ot; list

Bo?tjan Jerko <bostjan.jerko@ mf.uni-lj.si> wrote in message news:<mailman.1 154.1075795507. 12720.python-list@python.org >...[color=blue]
> Hello!
>
> I have a list of lists (e.g. [[1,"a"],[2,"b"],[3,"c"]]) and
> would like to do index on the first element of the lists.
> Can it be done?[/color]

I think you might want to try using dicts.
[color=blue][color=green][color=darkred]
>>> d = {1: 'a', 2: 'b', 3: 'c'}
>>> d[2][/color][/color][/color]
'b'

If you already have a list of lists, you can convert it to a dict with
the constructor.
[color=blue][color=green][color=darkred]
>>> a = [[1, "a"], [2, "b"], [3, "c"]]
>>> d = dict(a)[/color][/color][/color]