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Re: Newbie looking for elegant solution

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Date Wed, 25 Mar 2015 16:05:05 +1100
Subject Re: Newbie looking for elegant solution
From Chris Angelico <rosuav@gmail.com>
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On Wed, Mar 25, 2015 at 3:46 PM,  <kai.peters@gmail.com> wrote:
> Now I have just read the latest spec and speed/memory may become issues:
>
> 1 bit images of a size of 1024 x 1280 need to be processed this way, so
> 1310720 list elements. Also needs to be 2.7 only.
>
> Any recommendations?

2.7 only? Then my solution won't work (I just tried to port it, and
integers don't have to_bytes). Paul's solution works. Here's an
alternative:

>>> import numpy
>>> list(numpy.packbits(numpy.array(l),-1))
[177, 105, 117]

Of course, this does mean installing numpy. It is crushing the nut
with the triphammer - an absurd extravagance of energy, but the nut is
effectively crushed all the same.

ChrisA

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Newbie looking for elegant solution otaksoftspamtrap@gmail.com - 2015-03-24 20:13 -0700
  Re: Newbie looking for elegant solution Chris Angelico <rosuav@gmail.com> - 2015-03-25 14:28 +1100
    Re: Newbie looking for elegant solution otaksoftspamtrap@gmail.com - 2015-03-24 20:31 -0700
  Re: Newbie looking for elegant solution Paul Rubin <no.email@nospam.invalid> - 2015-03-24 21:04 -0700
    Re: Newbie looking for elegant solution kai.peters@gmail.com - 2015-03-24 21:19 -0700
    Re: Newbie looking for elegant solution Chris Angelico <rosuav@gmail.com> - 2015-03-25 15:19 +1100
      Re: Newbie looking for elegant solution kai.peters@gmail.com - 2015-03-24 21:46 -0700
        Re: Newbie looking for elegant solution Chris Angelico <rosuav@gmail.com> - 2015-03-25 16:05 +1100
        Re: Newbie looking for elegant solution Ben Finney <ben+python@benfinney.id.au> - 2015-03-25 16:28 +1100
        Re: Newbie looking for elegant solution Paul Rubin <no.email@nospam.invalid> - 2015-03-24 22:52 -0700
          Re: Newbie looking for elegant solution Rustom Mody <rustompmody@gmail.com> - 2015-03-24 23:32 -0700
  Re: Newbie looking for elegant solution Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-03-25 16:24 +1100
  Re: Newbie looking for elegant solution Dave Farrance <DaveFarrance@OMiTTHiSyahooANDTHiS.co.uk> - 2015-03-25 06:05 +0000
  Re: Newbie looking for elegant solution Travis Griggs <travisgriggs@gmail.com> - 2015-03-25 11:49 -0700
  Re: Newbie looking for elegant solution kai.peters@gmail.com - 2015-03-25 16:14 -0700
    Re: Newbie looking for elegant solution Paul Rubin <no.email@nospam.invalid> - 2015-03-25 16:30 -0700
    Re: Newbie looking for elegant solution Irmen de Jong <irmen.NOSPAM@xs4all.nl> - 2015-03-26 00:34 +0100
  Re: Newbie looking for elegant solution kai.peters@gmail.com - 2015-03-25 17:38 -0700
    Re: Newbie looking for elegant solution Paul Rubin <no.email@nospam.invalid> - 2015-03-25 18:09 -0700
      Re: Newbie looking for elegant solution kai.peters@gmail.com - 2015-03-25 18:29 -0700
        Re: Newbie looking for elegant solution Paul Rubin <no.email@nospam.invalid> - 2015-03-25 19:53 -0700

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