list organization question
Joe Strout
joe at strout.net
Thu Dec 11 18:21:47 EST 2008
On Dec 11, 2008, at 4:12 PM, Robocop wrote:
> I have a list of objects, each object having two relevant attributes:
> date and id. I'd like not only organize by id, but also by date.
> I.e. i would like to parse my list into smaller lists such that each
> new mini-list has a unique date, but consists of only objects with a
> specific id.
I'm not quite following you here. What are the inputs and outputs
you're after?
For the sake of argument let's say you want: given the list of objects
(let's call it mylist), and a desired ID (desired_id), return a
smaller list of all the objects with that ID. That would be simply:
return [item for item in mylist if item.id=desired_id]
Look up "list comprehensions" for an explanation of what's going on
here.
If you want a list for a given date, then just change the "if" part.
You seem to want both at once, but I can't understand what that means.
HTH,
- Joe
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