[clean-list] Re: Functions that look the same (clean-list digest)

[siegfried gonzi]

----- Original Message -----
From: <clean-list-admin@cs.kun.nl>
> From: smithll <smithll@cpsc.ucalgary.ca>

> reduce:: (Real -> Real)
> reduce = \x->x/10.0
>
> Start = until ((==)0.0 o \x->x/10.0) reduce 1.0
> will evaluate to 0
> while
> Start = until ((==)0.0 o reduce) (reduce) 1.0
> will evaluate to  0e-324

Postscript.

I tried the same on my Macintosh (Power PC 603e).

In both cases I got as answer: 9.88131291682493e-324

I did a small C program with MPW (the Apple native C/C++ compiler):

#include <stdio.h>
int main( void )
{
    double reduce1 = 1.0;
    double reduce2;
    do
    {
        reduce1 = reduce1/10.0;
        reduce2 = reduce1/10.0;
        printf("erg ist: %1.14e\n", reduce2);
    }while (reduce2 > 0.0)
}

That program delivers as results (notice %1.14e in printf):
...
9.88131291682493e-323
9.88131291682493e-324
0.00000000000000e+00

One thing bothers me is the observation that Clean only turns over the
double-results with 14 significant places.


S. Gonzi