On 2013-03-21, Troy Weber <gameslammer7 at gmail.com> wrote:
> I'm interested in contributing to the laplacian functions within Maxima.
> Specifically "ilt", which currently does not support "unit_step" or
> "delta". From a vibrations standpoint, this is an absolute must-have.
>
> Most of the answers online simply say "ilt doesn't support what you're
> looking for; read the documentation" which indicates to me that no one is
> planning on working on it. Well, I'm potentially willing to go through the
> grunt work, I just need a little help on finding out how I can contribute
> to official Maxima code and functions so that everyone can benefit.
>
> Can someone help me out with this, or direct me to a link that
> walks contributor's through how to modify and submit working code? I'm used
> to using Mercurial, but if I needed to learn Git, I could probably adapt.
Troy, thanks for your interest in Maxima. Some work was already done by
Mark Weaver some time ago [1, 2] to implement an inverse Laplace
transform for the Heaviside step function. I merged Mark's work into
Maxima and put the result on a Git branch named
origin/laplace-hstep-branch. I'll be frank and say that I'm not sure
what is a suitable incantation to retrieve it, as I don't want to lead
you astray (so often the case with Git). I hope someone else knows.
Can you take a look at laplace-hstep-branch and let us know what you
think? Ideally you could construct some test cases -- all you need are
pairs of expressions in a file (say rtest_foo.mac) and then
batch ("rtest_foo.mac", test);
evaluates the first expression and compares the result to the second.
If you have a typical GNU Autotools installation and some Lisp installed
(Clisp, CMUCL, SBCL, GCL, ECL, or Clozure CL), building Maxima should be
straightforward:
$ git <whatever>
$ sh bootstrap
$ ./configure --enable-$FOOLISP # where FOOLISP is a Lisp implementation
$ make
$ sh ./maxima-local # launch Maxima command line
best
Robert Dodier
[1] http://www.ma.utexas.edu/pipermail/maxima/2011/024967.html
[2] http://www.ma.utexas.edu/pipermail/maxima/2011/024968.html