On Thu, Dec 5, 2013 at 7:33 PM, <josef.p...@gmail.com> wrote: > On Thu, Dec 5, 2013 at 5:37 PM, Sebastian Berg > <sebast...@sipsolutions.net> wrote: >> Hey, >> >> there was a discussion that for numpy booleans math operators +,-,* (and >> the unary -), while defined, are not very helpful. I have set up a quick >> PR with start (needs some fixes inside numpy still): >> >> https://github.com/numpy/numpy/pull/4105 >> >> The idea is to deprecate these, since the binary operators |,^,| (and >> the unary ~ even if it is weird) behave identical. This would not affect >> sums of boolean arrays. For the moment I saw one "annoying" change in >> numpy, and that is `abs(x - y)` being used for allclose and working >> nicely currently. > > I like mask = mask1 * mask2 > > That's what I learned working my way through scipy.stats.distributions > a long time ago.
* is least problematic case, since there numpy and python bools already almost agree. (They return the same values, but numpy returns a bool array instead of an integer array.) On Thu, Dec 5, 2013 at 8:05 PM, Alan G Isaac <alan.is...@gmail.com> wrote: > For + and * (and thus `dot`), this will "fix" something that is not broken. > It is in fact in conformance with a large literature on boolean arrays > and boolean matrices. Interesting point! I had assumed that dot() just upcast! But what do you think about the inconsistency between sum() and dot() on bool arrays? -n _______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@scipy.org http://mail.scipy.org/mailman/listinfo/numpy-discussion
