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+--- Thread: Odd pow Behavior (/thread-13612.html)
Odd pow Behavior - ichabod801 - Oct-23-2018
I was doing some unit testing and came across something odd:
>>> -2 ** 4 -16 >>> pow(-2, 4) 16 >>> import operator >>> operator.pow(-2, 4) 16 >>> import math >>> math.pow(-2, 4) 16.0All of the documentation says that the various pow functions are equivalent to x ** y. However, the function call changes the order of operations. The negation is carried out when the number is evaluated as a parameter, instead of after the ** operator. So the pow functions are really calculating (x) ** (y), which is slightly different.
RE: Odd pow Behavior - micseydel - Oct-23-2018
That doesn't seem odd to me. It's just operator precedence. I might agree though that the exact docs should be updated.
I was more surprised that math.pow has a float result for what could have been an int, whereas the previous results all stayed ints.