On Nov. 16, 2010, Jaap Leguijt wrote:
----- Original Message -----
I recently had a problem for which I need to
be able to specify differential operators.
I want to use these to examine some approximations
that are used for the wave equation.
I did not find a convenient way to specify
these operators. [ ....]
Do you know a way to specify differential operators in Maxima?
Kind regards,
Jaap Leguijt
Principal Geophysicist
Shell International Exploration and Production B.V.
Volmerlaan 8, Postbus 60, 2280 AB Rijswijk, The Netherlands
Tel: ++31 70 4473032 2980
Email: jaap.leguijt at shell.com
Internet: http://www.shell.com/eandp-en
------------------------------------
Hi Jaap,
In my Maxima by Example, Ch. 6, Differential Calculus, I
consider a variety of simple uses of Maxima's diff function.
I have NOT included (yet) a section on the construction and
use of formal differential operators, including use of
the pdiff package.
A relatively painless way to find previous discussions
of such topics is to search the Maxima mailing list
archive by subject, at
http://www.math.utexas.edu/pipermail/maxima/
A search by subject of the 2010 archive, first for
<differential operator> (I use Firefox) finds the beginning
of a thread at
http://www.math.utexas.edu/pipermail/maxima/2010/020826.html
In that thread, the pdiff package is mentioned.
A search of the same archive for <pdiff> leads to the thread
starting at
http://www.math.utexas.edu/pipermail/maxima/2010/020594.html
pdiff.lisp is a package by Barton Willis, and you can find a pdf file
introduction in : ...\share\contrib\pdiff\pdiff-doc.pdf.
There are real experts, on the Maxima mailing list, on almost any
programming subject. Refine your desires into a small toy
problem with specific objectives, and show what progress
you have or have not made, using the display2d:false setting,
in your note to the mailing list for further suggestions.
Best Wishes,
Ted Woollett
http://www.csulb.edu/~woollett