Teaching differential equations with Maxima



> > those packages were written for the commercial Macsyma...
> disappointing for me since it forbids me to distribute these
> files to my students, since they belong to the commercial
> Macsyma.

Niko, I think you are confusing two meanings of the word "for".  I
believe Wolfgang meant that the packages were written to be compatible
with commercial Macsyma, because they were developed by users of
commercial Macsyma.  I do not believe he means that they were written
for the account of Macsyma Inc (although that may be the case for some
of them).

Just because something was written "for" the commercial Macsyma does not
mean that it is part of commercial Macsyma.  There are many packages
that were written "for" Macsyma by people outside Macsyma, Inc, which
never belonged to Macsyma, Inc, and which cannot be restricted by
Macsyma Inc licenses.

So we need to look at the situation in more detail.

Those files which do have Macsyma Inc copyright notices can be presumed
to have license restrictions.  However, some of them may have been
originally contributed to Macsyma by outside developers, who retain
their own rights.  The Share directories of Maxima/Macsyma contain many
contributed programs, which we might be able to get permission to use.

Some files have non-Macsyma Inc copyright notices.  We can try
contacting the authors for permission.  For example, symmgrp.max is
apparently copyrighted by P. Winternitz and colleagues at the Universit

And some files have no copyright notices.  Though they may still be
copyrighted under current law, I think it is both legal and ethical to
use them, since they are posted in public places, unless and until the
copyright owner asks us to stop.

Perhaps we need to establish some sort of registry of Maxima-compatible
software where we can keep track of who wrote what and what the license
conditions are.

     -s