Name: Vladyslav Shtabovenko Date: 09/16/15-12:44:42 AM Z
Dear all,
sorry for the late reply, at the moment I’m a bit busy finishing one
important calculation.
As Rolf wrote, Calc uses PowerSimplify which uses PowerExpand. The
latter can either assume that everything is real (default behaviour)
or
use general expansion formulas if the arguments might be complex
(which
we have now). Unfortunately, in this case PowerExpand doesn’t take
$Assumptions into account.
I think that the simplest solution would be to make Calc and
PowerSimplify accept the Assumptions option which will be then passed
to
PowerExpand. Then it will be up to the user to specify the
assumptions.
As a workaround for now,
Sqrt[x - 1] // Calc // Simplify
returns the correct result, as Simplify always honors $Assumptions.
I’ll fix this soon.
Cheers,
Vladyslav
Am 14.09.2015 um 10:58 schrieb Rolf Mertig:
> This is due to me. Sorry.
>
> Somehwere internally PowerSimplify is used which assumes all
variables are real. Maybe this assumption is not correct in general, of
course. I mentioned this to Vladyslav and he will look into how to fix
this. Sorry, but I have no time right now.
>