Thanks Chris Angelico for your nice answer. I got some sense, but could not imagine if required Bit No. 2–5, and Bit Combination 0000.
I hope example with the new case would make me more sense. Artur On Sat, Oct 18, 2014 at 3:24 PM, Chris Angelico <ros...@gmail.com> wrote: > On Sat, Oct 18, 2014 at 4:58 PM, Artur Bercik <vbubbl...@gmail.com> wrote: > > I want to get the index of my data where the following occurs: > > > > Bit No. 0–1 > > Bit Combination: 00 > > So, what you want to do is look at each number in binary, and find the > ones that have two zeroes in the last two places? > 1073741824: 1000000000000000000000000000000 > 1073741877: 1000000000000000000000000110101 > > The easiest way to do this is with simple bitwise operations: > > >>> 1073741824 & 3 > 0 > >>> 1073741877 & 3 > 1 > > 3 is 0000000000000011 in binary, so a bitwise AND with that will tell > you about just the last two bits. The result will be an integer - 0, > 1, 2, or 3, representing 00, 01, 10, or 11 for those last two bits. So > all you have to do is AND each number with 3, and when the result is > 0, that's what you want. > > Does that make sense? > > ChrisA > -- > https://mail.python.org/mailman/listinfo/python-list >
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