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Re: Newbie looking for elegant solution

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On Tuesday, 24 March 2015 21:04:37 UTC-7, Paul Rubin  wrote:
> nobody writes:
> > I have a list containing 9600 integer elements - each integer is
> > either 0 or 1.
> 
> Is that a homework problem?  This works for me in Python 2.7 but I think
> Python 3 gratuitously broke tuple unpacking so it won't work there:
> 
> ================================================================
> 
> from itertools import count, groupby
> old = [0, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 0, 1, 0, 1]
> new = [reduce(lambda x,(y,i):x*2+y, g, 0)
>        for k,g in groupby(zip(old,count()), lambda (a,b): b//8)]
> print new
> 
> >>> [18, 222, 53]
> ================================================================

no homework - real life. thanks for your contribution 

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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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