Teaching differential equations with Maxima

"Nikolaos I. Ioakimidis" <ioakimidis@otenet.gr> writes

> > `Of course, those packages were written for the commercial 
> > Macsyma . . .'
> 
> which is, to be sincere, disappointing for me since it forbids me
> to distribute these files to my students, since they belong to the
> commercial Macsyma. I have also been able to verify in some
> of them not only the Copyright sign by the authors prohibiting
> reproduction, but also the additional sign.
> 
> MACSYMA copyright and trademark: Macsyma, Inc.,
> Arlington, Ma, USA

The file

ftp://ftp.mines.colorado.edu/pub/papers/math_cs_dept/software/readme.now

states that the following form of copyright applies to all packages in
the sub-directories:

         You are welcome to use any of the software packages free of
         charge for scientific work, with acknowledgement of the
         developers and proper reference to either our research papers
         or to the software, or to both.

         The software may not be reproduced or sold without written
         consent of the authors (Copyright 1995-2002).

I think that your intended use qualifies as `scientific work' (even if
you described it mainly as a didactic effort).  I am a bit puzzled
about the `may not be reproduced', though, since down-loading (which
clearly is allowed for this form of use) is also a form of
reproduction, after all.

In my opinion, the Macsyma copyright and trademark notice you cite
applies only to the Macsyma program itself and not to the packages.

As Stavros has already remarked, by `written for Macsyma' I only meant
that these files might contain certain syntactical constructs or refer
to certain features which are not available in Maxima.  Hence my
surprise that at least the one test case I tried worked without
further ado.

I never used a commercial Macsyma, so I don't know where serious
compatibility issues are most likely to arise.  On the other hand, I
do have a (very good) book called `Macsyma Version 2' (by Stefan Braun
and Harald Häuser, Addison-Wesley 1995, in German) and, except for the
graphical user interface, I am not aware of Maxima lacking any major
feature they describe.  So I am rather optimistic about portability.

Wolfgang