On Thursday, October 25, 2012 7:56:25 AM UTC-7, Charles Hixson wrote: > In Python3 is there any good way to count the number of on bits in an > integer (after an & operation)?
You may want to look at gmpy2[1] and the popcount() function. > > 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, > Whether or not gmpy2 is considered light-weight is debateable. :) > 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? > [1] http://code.google.com/p/gmpy/ > > > -- > > Charles Hixson -- http://mail.python.org/mailman/listinfo/python-list