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From: kend@data.UUCP (Ken Dickey)
Newsgroups: comp.lang.lisp,comp.lang.scheme
Subject: Numerical Gotcha's ...addendum
Keywords: Interval Arithmetic, Bignums, Rationals, FLonums
Message-ID: <433@data.UUCP>
Date: 27 Nov 90 20:22:19 GMT
Organization: Microcosm, Beaverton, OR
Lines: 46


Numerical Results addendum...

===================
Vax Lisp 2.2 under Ultrix:

(f 77617   33096)	 -54767/66192
(f 77617e0 33096)	 -6.338253e29
(f 77617   33096e0) ... floating overflow on (expt 33096.0 8)
(f 77617d0 33096)	  1.172603940053179d0
(f 77617   33096d0)	 -1.180591620717411d21
(f 77617l0 33096l0)	  1.17260394005317863185883490452018L0

===================
MIT C-Scheme running under HP-UX
  Microcode 11.56
  Runtime 14.104

on an HP 9000s350 (Motorola MC68020 with MC68881 co-processor).

(f 77617  33096) 	 -54767/66192
(f 77617. 33096)	 -2.1002051317907482e20
(f 77617. 33096.)	 -1.390612063527742e21
(f 77617  33096.)	 -1.390612063527742e21

===================
Again (for comparison) Symbolics 3600 running Genera 8.0.  
"d"->double-precision; "e"->single-precision exponent

(f 77617d0 33096d0)	-1.1805916207174113d21
(f 77617e0 33096e0)	 6.338253e29
(f 77617   33096)	-54767/66192
(f 77617   33096e0)	 6.338253e29
(f 77617e0 33096)	-6.338253e29
(f 77617d0 33096)	-2.3611832414348226d21
(f 77617d0 33096e0)	 1.022335026998684d30
(f 77617e0 33096d0)	-2.0895373854550075d29

===================
In sending my original summary, I remarked that all implementations based 
on C lost.  After that, Guillermo J. Rozas (a.k.a. Bill, JINX) sent me the
new C-Scheme results.  My apologies.  The purpose of this exercise is to
promote better implementations.  My comment was not meant as a flame.

This was fun!  Let's do it again some time!
-Ken						kend@data.uucp