D(0^z, z)

(1)

Produced:

   >> Error detected within library code:
   Invalid argument

Of course, 0 is expected.

The offending code is in combfunc.spad, here is a patch. Note however, that strictly speaking 0^z is not differentiable at 0:

  @@ -405,7 +417,10 @@
         iipow l == ipow l

       if F has ElementaryFunctionCategory then
  -      dvpow2 l == log(first l) * first(l) ** second(l)
  +      dvpow2 l == if zero?(first l) then
  +                    0
  +                  else
  +                    log(first l) * first(l) ** second(l)

       evaluate(opfact, iifact)$BasicOperatorFunctions1(F)
       evaluate(oppow, iipow)

Martin

fixed in Feb 2005

Thu, 20 Jan 2005 10:43:06 -0600 reply