[Maxima] rootscontract(%i/2) -> -%i/2

[Barton Willis]

-----maxima-bounces at math.utexas.edu wrote: -----

>If we cut out the special substitution %i -> -1*(-1)^(-1/2) the errors
>will vanish. The testsuite and the share-testsuite have no problems. The
>only change is, that we no longer get the simplification %i/sqrt(x) ->
>-1/sqrt(-x).
>
>Furthermore, I think this simplification is in most cases not very
>useful.

>What do you think? Should we cut out this special case, which causes in
>most cases wrong results?

By itself, I don't think i/sqrt(x) -> -1/sqrt(-x) is useful. Maybe in
combination with some other term, it might be, but I doubt it. Since
the bug is not that difficult to trigger and it gives wrong results,
I suggest that you comment out the offending code and make a source
code comment about why the code was commented out.

Barton