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Re: Optimizing list processing

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Date Thu, 12 Dec 2013 02:09:42 +0000
From MRAB <python@mrabarnett.plus.com>
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Subject Re: Optimizing list processing
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On 12/12/2013 01:43, Steven D'Aprano wrote:
> On Thu, 12 Dec 2013 00:59:42 +0000, MRAB wrote:
>
>>> table = [(x, i) for i,x in enumerate(iterable)]
>>> table.sort()
>>
>> This looks wrong to me:
>>
>>> for x, i in table:
>>>      table[i] = x
>
> Yes, you're right, I over-simplified the example, and in doing so
> introduced a bug. What I actually use is:
>
> for i, x in enumerate(table):
>      table[i] = x[1]
>
> modulo any further bugs introduced while copying and pasting :-)
>
How does this compare:

table = list(iterable)
indexes = list(range(len(table)))
indexes.sort(key=table.__getitem__)

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Thread

Optimizing list processing Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-12-11 23:54 +0000
  Re: Optimizing list processing MRAB <python@mrabarnett.plus.com> - 2013-12-12 00:59 +0000
    Re: Optimizing list processing Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-12-12 01:43 +0000
      Re: Optimizing list processing MRAB <python@mrabarnett.plus.com> - 2013-12-12 02:09 +0000
  Re: Optimizing list processing duncan smith <buzzard@invalid.invalid> - 2013-12-12 01:02 +0000
  Re: Optimizing list processing Ben Finney <ben+python@benfinney.id.au> - 2013-12-12 12:18 +1100
  Re: Optimizing list processing Terry Reedy <tjreedy@udel.edu> - 2013-12-11 21:26 -0500
    Re: Optimizing list processing Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-12-12 12:08 +0000
      Re: Optimizing list processing Chris Angelico <rosuav@gmail.com> - 2013-12-12 23:25 +1100
      Re: Optimizing list processing MRAB <python@mrabarnett.plus.com> - 2013-12-12 13:32 +0000
      Re: Optimizing list processing Chris Angelico <rosuav@gmail.com> - 2013-12-13 01:06 +1100
      Re: Optimizing list processing Terry Reedy <tjreedy@udel.edu> - 2013-12-12 13:40 -0500
        Re: Optimizing list processing Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-12-13 00:14 +0000
          Re: Optimizing list processing Chris Angelico <rosuav@gmail.com> - 2013-12-13 12:01 +1100
  Re: Optimizing list processing Stefan Behnel <stefan_ml@behnel.de> - 2013-12-12 12:09 +0100
  Re: Optimizing list processing Peter Otten <__peter__@web.de> - 2013-12-12 16:08 +0100
    Re: Optimizing list processing Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-12-13 03:01 +0000
      Re: Optimizing list processing rusi <rustompmody@gmail.com> - 2013-12-12 21:35 -0800
  Re: Optimizing list processing Terry Reedy <tjreedy@udel.edu> - 2013-12-12 13:07 -0500

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