Re: [Axiom-math] Re: partfrac, expand, combine,rewrite and simplify.

[Dylan Thurston]

On Mon, Oct 13, 2003 at 08:33:42AM +0200, address@hidden wrote:
> Bill and Dylan, 
> 
> >   -> expandBinomial := rule binomial(n,(m | integer? m and m>1)) ==
> >        (n-m+1)/m*binomial(n,m-1)
> > 
> >   -> % :: UP(x,FRAC INT)
>  
> I cut/copy your command in _one_ line and get an error :
> What must I change ?
> 
> (1) -> expandBinomial := rule binomial(n,(m | integer? m and m>1)) == 
> (n-m+1)/m*binomial(n,m-1)
>
>    The form on the left hand side of an assignment must be a single 
>       variable, a Tuple of variables or a reference to an entry in an 
>       object supporting the setelt operation.

That isn't what I got:

(12) -> expandBinomial := rule binomial(n,(m | integer? m and m>1)) == 
(n-m+1)/m*binomial(n,m-1)

          n     (n - m + 1)'binomial(n,m - 1)
   (12)  ( ) == -----------------------------
          m                   m
                        Type: RewriteRule(Integer,Integer,Expression Integer)

Are you using a build of Axiom with all the algebra included?  Since one
of the missing files was the combinatorial functions, you're sure to have
trouble then.  (However, I got a different error message.)

> How computes the rule command ?

You mean how to use it?  I'm not sure; I thought I saw it in the
tutorial, but I can't find it now.

Peace,
        Dylan