unique values of a Dictionary list (removing duplicate elements of a list)

[Chad Kellerman]

On Fri, May 21, 2010 at 8:07 AM, Chad Kellerman <sunckell at gmail.com> wrote:

>
>
> On Fri, May 21, 2010 at 7:50 AM, Peter Otten <__peter__ at web.de> wrote:
>
>> Chad Kellerman wrote:
>>
>> > Python users,
>> >       I am parsing an AIX trace file and creating a dictionary
>> containing
>> > keys (PIDS) and values (a list of TIDS).  With PIDS being unique process
>> > ids
>> > and TIDS, being a list of thread ids.  My function populates the keys so
>> > that they are unique, but my list contains duplicates.
>> >
>> >      Can someone point me in the right direction so that my dictionary
>> >      value
>> > does not contain duplicate elements?
>> >
>> >
>> > here is what I got.
>> >
>> > --------------<portion of code that is relevant>------------------
>> >
>> > pidtids  = {}
>> >
>> > # --- function to add pid and tid to a dictionary
>> > def addpidtids(pid,tid):
>> >     pidtids.setdefault(pid,[]).append(tid)
>>
>> Use a set instead of a list (and maybe a defaultdict):
>>
>> from collections import defaultdict
>>
>> pidtids = defaultdict(set)
>>
>> def addpidtids(pid, tid):
>>    pidtids[pid].add(tid)
>>
>> Peter
>>
>
> Thanks.  I guess I should have posted this in my original question.
>
> I'm on 2.4.3  looks like defautldict is new in 2.5.
>
> I'll see if I can upgrade.
>
> Thanks again.
>


 instead of upgrading.. (probably be faster to use techniques in available
2.4.3)

Couldn't I check to see if the pid exists (has_key I believe) and then check
if the tid is a value, in the the list for that key, prior to passing it to
the function?

Or would that be too 'expensive'?


>
>
>
>>
>> --
>>
>> http://mail.python.org/mailman/listinfo/python-list
>>
>
>
>
> --
> A grasshopper walks into a bar and the bartender says "Hey, we have a drink
> named after you." And the grasshopper says "Really, You have a drink named
> Murray?"
>



-- 
A grasshopper walks into a bar and the bartender says "Hey, we have a drink
named after you." And the grasshopper says "Really, You have a drink named
Murray?"
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20100521/909cf5fe/attachment.html>