[Numpy-discussion] Should bool_ subclass int?
Gael Varoquaux
gael.varoquaux@normalesup....
Tue Jul 10 11:00:42 CDT 2007
On Tue, Jul 10, 2007 at 11:31:35AM -0400, Alan G Isaac wrote:
> Do you agree that the first (!!!) answer is a bug?
> (The basis is apparently performed as follows:
> integer array subtraction is first performed, and
> then nonzero ints are converted to True. But this
> gives the wrong answer and most critically breaks
> the equivalence of a-b and a+(-b).)
OK, putting aside the useless maths, I agree that specifically having
a-b != a+(-b)
If numpy developpers agree, I think the proper solution is :
"""
def __sub__(self, b):
return self.__add__(-b)
"""
I think to should allow to have more or less consistent operations.
Gaël
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