From: Jentje Goslinga
Newsgroups: sci.math.symbolic
Subject: Re: How good is Macsyma?
Date: Mon, 20 Oct 1997 23:44:56 -0600
lbliao wrote:
> I am looking at various symbolic manipulation programs, such as Macsyma. I
> would like to get opinions from people who have used it on its quality, and
> what they found good or poor about it. If you can compare it with other
> free and commercial symbolic manipulation programs, that would be great!
> thanks
> lbliao
I have used Macsyma for 5 years and have been able to solve at least
part of the problems I have thrown at it.
How good is it ?
The answer is: what dou you want to do ?
Both REDUCE and Macsyma have been around for a long time
and seem to be quite stable. Maple and Mathematica are of more
recent date.
The well known benchmark comparing symbolic algebra packages is
available by ftp but it only tests fairly trivial computations, not ones
requiring programs.
From what I have heard, it seems that for the occasional Taylor
expansion, indefinite integral or symbolic matrix inversion any of
the well known packages such as Maple, Macsyma or Mathematica
will do.
I have written many programs using subroutines in Macsyma for a
variety of problems. These include symbolic matrices of orders
three to five or rational number matrices of order 20 or so and also
some graphics. I have also used indicial tensor algebra and performed
error analysis for numerical problems.
Matrix algebra in Macsyma is reasonibly well supported.
However, matrices have indices that start at one and they are
different from arrays which start at zero and again different from lists.
In addition to tensors of fixed order (e.g. 3-4)as used in classical
differential
geometry and relativity, Macsyma also handles indicial tensors.
I have heard that REDUCE also handles tensors well but that
Mathematica requires and add-on package.
The graphics are reasonable but not as good as Mathematica's.
I have heard that REDUCE is mainly symbolic and has no graphics.
I have done hand calculation all my life and have considerable difficulty
making Macsyma (and probably any other symbolic program) do what
I want. If you have never done calculations by hand, it will even be harder.
Common difficulties involve the cancellation of radicals, the recovery of sums
of terms after expansion, and the problem of substitution. It is not unusual
to work through a complex calculation one step at a time.
I think none of the symbolic programs is easy to use as advertised.
Macsyma has the concept of a notebook which is largely useless for anything
but trivial problems. The only practical way is to use a batch file to store
your
commands and edit it with an editor and reexecute it. Furthermore, I have
owned Macsyma for about four years now and have not observed any changes
or improvements in the mathematics engine but only "Windows dressing" and
additional numerical capabilities such as a PDE solver.
Mathematica on the other hand is quickly catching up thanks to an agressive
marketing campaign and a very high price tag.
You can also visit the sites:
The Benchmark
http://www.numerik.uni-kiel.de/faqs/tda/q520.1.html
Macsyma
http://www.macsyma.com
Maple
http://www.maplesoft.com
Mathematica
http://www.wri.com
REDUCE
http://www.rrz.uni-koeln.de/REDUCE
If you have any more questions about Macsyma let me know,
Jentje Goslinga