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bit count or bit set && Python3

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Date Thu, 25 Oct 2012 07:47:58 -0700
From Charles Hixson <charleshixsn@earthlink.net>
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In Python3 is there any good way to count the number of on bits in an 
integer (after an & operation)?
Alternatively, is there any VERY light-weight implementation of a bit 
set?  I'd prefer to use integers, as I'm probably going to need 
thousands of these, if the tests work out.  But before I can test, I 
need a decent bit counter.  (shift, xor, &, and | are already present 
for integer values, but I also need to count the number of "true" items 
after the logical operation.  So if a bitset is the correct approach, 
I'll need it to implement those operations, or their equivalents in 
terms of union and intersection.)

Or do I need to drop into C for this?

-- 
Charles Hixson

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Thread

bit count or bit set && Python3 Charles Hixson <charleshixsn@earthlink.net> - 2012-10-25 07:47 -0700
  Re: bit count or bit set && Python3 rusi <rustompmody@gmail.com> - 2012-10-25 09:13 -0700
    Re: bit count or bit set && Python3 Terry Reedy <tjreedy@udel.edu> - 2012-10-25 16:16 -0400
  Re: bit count or bit set && Python3 Christian Gollwitzer <auriocus@gmx.de> - 2012-10-25 19:25 +0200
    Re: bit count or bit set && Python3 Ian Kelly <ian.g.kelly@gmail.com> - 2012-10-25 12:19 -0600
  Re: bit count or bit set && Python3 casevh@gmail.com - 2012-10-26 08:42 -0700
    Re: bit count or bit set && Python3 Charles Hixson <charleshixsn@earthlink.net> - 2012-10-26 09:30 -0700
  Re: bit count or bit set && Python3 casevh@gmail.com - 2012-10-26 08:42 -0700

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