Mathematics in Python are not correct

[Arnaud Delobelle]

On 12 May, 15:21, Mark Dickinson <dicki... at gmail.com> wrote:
> On May 12, 2:09 am, "Terry Reedy" <tjre... at udel.edu> wrote:
>
> > Then it seems equally dubious that 0.**y, y>0, should be well-defined.
> > It seems to me that lim as x goes to 0. exp(y*log(x)) is equally well
> > defined whether y is 0 or not, even though there is a discontinuity in the
> > limit.
>
> Well, there's a difference:  the limit of exp(y*log(x)) as (x, y) ->
> (0, a) exists for all finite nonzero a.  The limit as (x, y) ->
> (0, 0) doesn't.

But exp(y*log(x)) -> 1 as (x, y) -> (0, 0) along any analytic curve
which is not the x=0 axis (I think at least - it seems easy to prove
that given f and g analytic over R, f(x)*ln g(x) -> 0 as x -> 0 if
f(0)=g(0)=0 and g(x)>0 in the neighbourhood of 0).  This should cover
most practical uses?

--
Arnaud