Re: Avoid treating the stack as an array [Re: "Back & Forth" is back!]

melahi_ahmed@yahoo.fr (Ahmed) writes:

Hi,
In fuzzy logic, a triangular membership function mf(x;a,b,c) is defined
as:
>
mf(x;a,b,c) = (x-a)/(b-a) for a <= x < b,
             (c-x)/(c-b) for b <= x < c,
             0e elsewere.
>
defining it with locals:
>
: tri_mf() { f: x f: a f: b f: c } ( f: x a b c -- mv)
    x a f>= x b f< and if x a f- b a f- f/ exit then
    x b f>= x c f< and if c x f- c b f- f/ exit then
    0e
;
>
But defining it without locals ????!!!!!
>
: tri_mf() ( f: x a b c -- mv) ....
>
How?

I wonder if the notation "mf(x;a,b,c)" indicates that a,b,c is a tuble
that tends to get passed around without changing it.  In that case
defining it as a structure in memory and accessing its members there
might be a solution.

But OTOH, unless you see programming in Forth as a religious exercise,
why worry, as long as your solution works.

- anton
--
M. Anton Ertl  http://www.complang.tuwien.ac.at/anton/home.html
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