Edit detail for #19 D(0^z, z) fails revision 1 of 2

changed:
-
\begin{axiom}
D(0^z, z)
\end{axiom}

Produced::

   >> Error detected within library code:
   Invalid argument

Of course, 0 is expected.




From kratt6 Thu Jan 20 07:29:04 -0600 2005
From: kratt6
Date: Thu, 20 Jan 2005 07:29:04 -0600
Subject: patch
Message-ID: <20050120072904-0600@page.axiom-developer.org>

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

From unknown Thu Jan 20 10:43:06 -0600 2005
From: 
Date: Thu, 20 Jan 2005 10:43:06 -0600
Subject: fixed in Feb 2005 
Message-ID: <20050120104306-0600@page.axiom-developer.org>

Status: open => closed 

Submitted by : (unknown) at: 2007-11-17T22:07:07-08:00 (17 years ago) Name : Axiom Version : default friCAS-20090114 Axiom-20050901 OpenAxiom-20091012 OpenAxiom-20110220 OpenAxiom-Release-141 Category : general Severity : critical serious normal minor wishlist Status : open pending closed Optional subject :   Optional comment :

axiom
D(0^z, z)

(1)

Type: Expression Integer

Produced:

   >> Error detected within library code:
   Invalid argument

Of course, 0 is expected.

patch --kratt6, Thu, 20 Jan 2005 07:29:04 -0600 reply

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

Status: open => closed