On Sat, Feb 18, 2017 at 12:04 AM, Alan Isaac <alan.isaac@gmail.com> wrote:
http://python-history.blogspot.com/2010/08/why-pythons- integer-division-floors.html
I need floor division for the remaining computation, so that part I'm happy with.(Actually, when I start to use divmod I have only non-negative numbers)
bwi = 5 np.arange(-bwi // 2, bwi // 2 + 1) array([-3, -2, -1, 0, 1, 2]) np.arange(-(bwi // 2), bwi // 2 + 1) array([-2, -1, 0, 1, 2])
the bug hunting was: Why is the window asymmetric? What threw me off is the operator precedence, what Robert said about operator precedence is kind of obvious ex-post, but the case where it matters doesn't show up often enough to automatically think about it, and the familiar float analogy doesn't apply. e.g. I avoid remembering some rules by using explicit, defensive parenthesis
1.5**(-2)
it's commutative
--2 / -3 -0.6666666666666666 ---2 / 3 -0.6666666666666666 ---(2 / 3) -0.6666666666666666
Josef
fwiw, Alan _______________________________________________ SciPy-Dev mailing list SciPy-Dev@scipy.org https://mail.scipy.org/mailman/listinfo/scipy-dev