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Date: Wed, 24 Oct 2012 19:19:55 -0700
From: Charles Hixson <charleshixsn@earthlink.net>
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To: python-list@python.org
Subject: bit count or bit set && Python3
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Xref: csiph.com comp.lang.python:32169

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