Peter Otten wrote:
> Here is another implementation that cuts maximum memory down from 100 to
> 50%.
>
> from itertools import islice
> def swap(items):
> items[::2], items[1::2] = islice(items, 1, None, 2), items[::2]
> return items
Unfortunately, the following
>>> a = [1, 2, 3]
>>> a[
Steven D'Aprano wrote:
> On Thu, 30 Nov 2006 11:17:17 +0100, Peter Otten wrote:
>
>> Steven D'Aprano wrote:
>>
>>> And remember that if alist is truly huge, you may take a performance hit
>>> due to duplicating all those megabytes of data when you slice it.
>>
>> Having the same object in two l
Steven D'Aprano <[EMAIL PROTECTED]> wrote:
> Everybody always forgets corner cases... like lists with odd number of
> items... *wink*
>
I didn't forget. I just assumed that raising an exception was a more useful
response.
> Here is a version that handles both odd and even length lists:
>
> def
On Thu, 30 Nov 2006 11:17:17 +0100, Peter Otten wrote:
> Steven D'Aprano wrote:
>
>> And remember that if alist is truly huge, you may take a performance hit
>> due to duplicating all those megabytes of data when you slice it.
>
> Having the same object in two lists simultaneously does not doub
Duncan Booth wrote:
> items[::2], items[1::2] = items[1::2], items[::2]
Cool. I really should have found that myself.
Peter
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Peter Otten <[EMAIL PROTECTED]> wrote:
> That example was chosen to prove your point. The real contender for the
> "swap items" problem are slices.
>
> def swap_slice(items):
> left = items[::2]
> items[::2] = items[1::2]
> items[1::2] = left
> return items
>
It makes no differ
