Thanks for your note. ** has priority over - in Perl, so -$x**2 ==
$x**2, the sqrt of which is both -$x and +$x. One of the failings of
Symbols is that it does not carry all radicles - it should recognize
that sqrt is multi valued and keep both possible results in play until
perhaps another **2 renders them moot.
[guest - Wed Aug 17 07:16:47 2005]:
Show quoted text> This sample is false:
>
> $x = symbols(qw(x));
> $z = sqrt(-$x**2);
> print "$z\n";
> # $i*$x
>
> since
> if x = -2
> result is -x * i (2*i)
>
> Cheers,
>
> Greg
RT for rt.cpan.org