[Axiom-developer] [#19 D(0^z, z) fails] patch

[kratt6]

??changed:
-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)
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)

--
forwarded from http://page.axiom-developer.org/zope/mathaction/address@hidden