I've done some web searching, and also some database searches, and can't
find anything about public Macsyma z-transform code. However, back in 1995,
some code was written for REDUCE:
http://www.zib.de/Symbolik/reduce/moredocs/ztrans.pdf
I have no idea of the differences between Macsyma and REDUCE, and how
non-trivial it would be to port REDUCE code to Maxima, but maybe it would be
worth a look... the first author is now at Universit?t Kassel:
http://www.mathematik.uni-kassel.de/~koepf/indexenglish.html
-Alasdair
On 1/27/07, Stavros Macrakis <macrakis at alum.mit.edu> wrote:
>
> On 1/26/07, Alasdair McAndrew <amca01 at gmail.com> wrote:
> > I think a symbolic z-transform would be a very welcome addition to
> Maxima.
> > I don't know if commercial Macsyma ever included z-transform routines,
> but
> > if so it should be possible to port them to Maxima (assuming that you
> can
> > obtain the source code).
>
> Well, if we could (legally) obtain the source code (whether in Lisp or
> in the Macsyma language) to commercial Macsyma, there are *many*
> things we could improve. But as far as I know, the copyright holder
> has no interest in releasing it under an free or open license.
>
> If, on the other hand, there is code developed for commercial Macsyma
> by *outside* developers, there is a chance they can be persuaded to
> contribute their code to the Maxima project.
>
> -s
>