Re: rule sets and patterns, was ...Re: [ Homological Algebra in Maxima]
Subject: Re: rule sets and patterns, was ...Re: [ Homological Algebra in Maxima]
From: Stavros Macrakis
Date: Sat, 14 Jun 2003 14:13:48 -0400
> it seems like Maxima's evaluation scheme is quite different
> than math'a (or yacas).... For example, if I do GCD[m,n]
The Maxima scheme is a bit messy and probably could use cleaning up.
Some operators (like GCD) are essentially executable functions (verbs),
others (like "*") are essentially mathematical structure-creators, and
many function as both (e.g. integrate, limit, etc.).
In theory, 'operator(...) gives you the noun form -- try 'gcd(m,n) --
but this scheme is not carried through consistently. In particular,
there are no simplifications available for the noun gcd, so you do NOT
get simplifications like 'gcd(1,n) => 1, 'gcd(n,n) => n, etc. Those are
only provided by the verb....
It's a mess.
I am leaving for vacation in a few hours and don't have time to discuss
this, but perhaps we can continue in a couple of weeks....
-s