Subject: What do you mean about this data structure
From: Richard Fateman
Date: Tue, 08 Mar 2005 11:59:37 -0800
laurent couraud wrote:
> Hi,
>
> First sorry for my bad English. I'm French
>
> Use fixed font to read this message please.
>
> I try to found the most efficient way to store CRE form of
> expression. In memory usage and speed access.
>
> "Classic" form of expression :
> x1*(x2^2+3*x3)+x1^2*x2^3-x1^(3*n)
>
This is a rational expression in x1, x2, x3 and (x1^n).
is that what you want?
to see its encoding, do
q:x1*(x2^2+3*x3)+x1^2*x2^3-x1^(3*n)$
:lisp $q
efficiency depends on what you intend to store (sparse, dense?)
and what you intend to do (multiply? divide?). Size is rarely
a problem now that memory is so cheap. Fast is usually better
than slow :)
RJF