Bizarre arithmetic results

[Shashwat Anand]

Do you really believe that -0.1 ** 0.1 is a valid computational problem ?
Can you raise a negative number to a fractional power ?
Output on my console (python 2.6)

>>> -.1 ** .1
-0.79432823472428149
>>> a,b = -.1,.1
>>> a**b
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: negative number cannot be raised to a fractional power
>>> -abs(a**b)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: negative number cannot be raised to a fractional power

There is a little issue here that '>>> -.1 ** .1' should give you error
message. That is it.


On Thu, Feb 11, 2010 at 6:14 AM, Terrence Cole <
list-sink at trainedmonkeystudios.org> wrote:

> Can someone explain to me what python is doing here?
>
> Python 3.1.1 (r311:74480, Feb  3 2010, 13:36:47)
> [GCC 4.3.4] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
> >>> -0.1 ** 0.1
> -0.7943282347242815
> >>> a = -0.1; b = 0.1
> >>> a ** b
> (0.7554510437117542+0.2454609236416552j)
> >>> -abs(a ** b)
> -0.7943282347242815
>
> Why does the literal version return the signed magnitude and the
> variable version return a complex?
>
> Cheers,
> Terrence
>
> --
> http://mail.python.org/mailman/listinfo/python-list
>
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