On 5/7/07, Daniel Lakeland <dlakelan at street-artists.org> wrote:
> matchdeclare(aa,atom,bb,atom,cc,atom);
>
> tellsimpafter(laplace(signum(aa-bb),aa,cc),exp(-bb*cc)/cc);
> laplace(signum(x-a),x,s);
>
> why doesn't tellsimpafter cause laplace(signum(x-a),x,s) to be
> converted to exp(-a*s)/s???
>
> I suspect it somehow has to do with the way that x-a is matched...
x - a is represented internally as x + (-1 * a).
Try writing signum(aa + bb) instead.
tellsimpafter handles + and * differently from other operators.
But maybe not when the main (top level) operator is not + or *.
Sorry to be vague; the code is confusing.
Also Maxima reorders + and * expressions. If order is important
you might try simp:false before the tellsimpafter.
> but the manual doesn't help me understand it.
I know this doesn't help, but tutorial stuff should be in documents
apart from the reference manual.
HTH
Robert