On Sat, May 24, 2008 at 7:36 PM, Robert Kern <[EMAIL PROTECTED]> wrote: > On Sat, May 24, 2008 at 9:28 PM, Keith Goodman <[EMAIL PROTECTED]> wrote: >> I think it's interesting how python and numpy bools behave differently. >> >>>> x = np.array([True, True], dtype=bool) >>>> x[0] + x[1] >> True >>>> x[0] & x[1] >> True >>>> >>>> x = [True, True] >>>> x[0] + x[1] >> 2 >>>> x[0] & x[1] >> True > > The difference arises straightforwardly from the principle that numpy > tries not to upcast when you do an operation on two arrays of the same > dtype; True+True==True is of somewhat more use than True+True==False. > Python bools are just ints subclasses to give a nice string > representation.
Sounds like there is no perfect solution. I like it the way it is but these are differences I never noticed. >> x = np.array([True, True], dtype=bool) >> x.sum() 2 >> x[0] + x[1] True _______________________________________________ Numpy-discussion mailing list Numpy-discussion@scipy.org http://projects.scipy.org/mailman/listinfo/numpy-discussion
