Subject: Re: set.lisp redefines POWERSET / {} for sets
From: Andreas J. Guelzow
Date: 05 Mar 2003 14:30:28 -0700
On Wed, 2003-03-05 at 11:06, Richard Fateman wrote:
> Using {} for sets would mean that no one could
> use it for anything else. This leads to difficulties.
>=20
> You may think it is standard to do {a,b,c} but
> what about
> {x in Z | prime(x) and x< 100}
> which also standardly uses {} but also |.
One of the (few) nice things about mupad is that it in fact allows both
{a,b,c} and a variant of {x in Z | prime(x) and x< 100} namely:
{2*i $ i=1..10}
So this does not need to be exclusive.
> {} () [] are also used in various combinatorial
> notations.
>=20
> "standard" math notation must be evaluated
> very carefully. It tends to be ambiguous
> without context.
But this still allows the argument that the most rudimentary use should
be the default one. We consciously overload certain notation in various
discipline but the base notation is usually the same.
Andreas
--
Andreas J. Guelzow <aguelzow@taliesin.ca>
Taliesin