I know it has nothing todo with linspace.
But there seems to be a link to using numpy generated variables and not using them.
From a naive point of view i’d expect the same results.
But it does not.
There is two functions, and two variables.
And from the four combinations, only one gives a non NAN error.

> On 12 Sep 2018, at 20:19, Steven D'Aprano <report@bugs.python.org> wrote:
> 
> 
> Steven D'Aprano <steve+python@pearwood.info> added the comment:
> 
>> Well, the thing is that i pass two (apparent) identical values into the same function,
> 
> Even if they have the same *numeric* value, they aren't the same kind of
> value, and they aren't the same function.
> 
> One is <type 'numpy.float64'> and the other is <class 'float'>. When you
> call ** (exponentiation), that calls two different methods. One raises
> a warning and returns NAN, the other converts to complex.
> 
> This has nothing to do with linspace. See my simplifed example code
> which doesn't use it.
> 
> ----------
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> Python tracker <report@bugs.python.org>
> <https://bugs.python.org/issue34645>
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