spliting a list by nth items
Steven Bethard
steven.bethard at gmail.com
Thu Sep 23 18:36:46 EDT 2004
Raymond Hettinger writes:
> The enumerate solution has a lot going for it. It is more flexible and
> easily accomodates criteria other than every nth item.
Yeah, I'm not so much worried about this, or I wouldn't be using
items[start::n]
to make the nth_items list in the first place. (If I was planning to allow
for other criteria, I'd probably use filter or ifilter instead of the
slicing...)
> More importantly, it demonstrates an important guiding principle: multiple
> list deletions are a code smell indicating that building a new list is a
> better approach.
This was kinda my feeling -- hence why I posted. Part of the problem for me
was that because the two lists were so closely related semantically, I was
looking for a syntax that was also closely related. Sometimes this is a good
intuition to have, sometimes not. ;)
> The runtime behavior of the non_nth_items[start::n] approach is
> implementation dependent.
Ahh, I didn't know that. Good thing to know...
Thanks,
Steve
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