how to iterate over several lists?

Chris Rebert clp2 at rebertia.com
Fri Jun 5 15:46:54 EDT 2009


On Fri, Jun 5, 2009 at 11:37 AM, Minesh Patel<minesh at gmail.com> wrote:
> On Fri, Jun 5, 2009 at 10:20 AM, Tom<sevenbark at gmail.com> wrote:
>> On Fri, 5 Jun 2009 04:07:19 +0000 (UTC), kj <no.email at please.post>
>> wrote:
>>
>>>
>>>
>>>Suppose I have two lists, list_a and list_b, and I want to iterate
>>>over both as if they were a single list.  E.g. I could write:
>>>
>>>for x in list_a:
>>>    foo(x)
>>>for x in list_b:
>>>    foo(x)
>>>
>>>But is there a less cumbersome way to achieve this?  I'm thinking
>>>of something in the same vein as Perl's:
>>>
>>>for $x in (@list_a, @list_b) {
>>>  foo($x);
>>>}
>>>
>>>TIA!
>>>
>>>kynn
>>
>> def chain(*args):
>>  return (item for seq in args for item in seq)
>>
>> for x in chain(list_a, list_b):
>>    foo(x)
>> --
>> http://mail.python.org/mailman/listinfo/python-list
>>
>
> If they are the same length, you can try the zip built-in function.

But he doesn't want to iterate over them in parallel...

Cheers,
Chris
-- 
http://blog.rebertia.com



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