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devel / comp.lang.python / Re: built-in pow() vs. math.pow()

Re: built-in pow() vs. math.pow()

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From: bar...@barrys-emacs.org (Barry)
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Subject: Re: built-in pow() vs. math.pow()
Date: Fri, 31 Mar 2023 07:39:25 +0100
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by: Barry - Fri, 31 Mar 2023 06:39 UTC

> On 30 Mar 2023, at 22:30, Chris Angelico <rosuav@gmail.com> wrote:
>
> On Fri, 31 Mar 2023 at 08:13, Oscar Benjamin <oscar.j.benjamin@gmail.com> wrote:
>>
>>> On Thu, 30 Mar 2023 at 17:31, Andreas Eisele <andreas.eisele@gmail.com> wrote:
>>>
>>> I sometimes make use of the fact that the built-in pow() function has an optional third argument for modulo calculation, which is handy when dealing with tasks from number theory, very large numbers, problems from Project Euler, etc. I was unpleasantly surprised that math.pow() does not have this feature, hence "from math import *" overwrites the built-in pow() function with a function that lacks functionality. I am wondering for the rationale of this. Does math.pow() do anything that the built-in version can not do, and if not, why is it even there?
>>
>> It is useful for when you want the pure floating point power which has
>> an approximately fixed computational cost (unlike integer powers).
>> Perhaps it would have been better if it was named fpow similar to fsum
>> vs sum.
>>
>
> It's called math.pow. That on its own should be a strong indication
> that it's designed to work with floats.

So long as you know that the math module is provided to give access the C math.h functions.

Barry

>
> ChrisA
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Subject	Author
Re: built-in pow() vs. math.pow()	Barry