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From: "Bob Binder  (remove .mapson to email)" <rbinder@rbsc.mapson.com>
Subject: Re: floating point comparison
Date: 1997/08/05
Date: 1997-08-05T00:00:00+00:00	[thread overview]
Message-ID: <01bca1a2$87d442a0$e1e989cc@gort> (raw)
In-Reply-To: 33E611E4.2E1A@pseserv3.fw.hac.com




W. Wesley Groleau x4923 <wwgrol@pseserv3.fw.hac.com> wrote in article
<33E611E4.2E1A@pseserv3.fw.hac.com>...
> > >> x, y float;
> > 
> > >> x = 1.0;
> > >> y = (x/10.0)*10.0;
> > >> if x == y {
> > >>         // not likely }
> > >> else {
> > >>         // more likely
> > >> };
> > >Although I am reading this in comp.lang.ada, the suggestion to try a
> > >simple example like this in C piqued my interest.
> >      You lucked out due to IEEE rounding to nearest.
>    [snip]
> >     On the other hand, try (1.0/49.0)*49.0.
> 
> 49 "works" in GNAT.  The following gets eight 'no' and 92 'yes' :
> 
> with Ada.Text_IO;
> procedure FP_Test is
>    ONE : constant Float := 1.0;
> begin
>    for I in 1 .. 100 loop
>       if ONE = ( ONE / Float(I) ) * Float(I) then
>         Ada.Text_IO.Put_Line ( Integer'Image(I) & ": YES !!" );
>       else
>         Ada.Text_IO.Put_Line ( Integer'Image(I) & ": no...." );
>       end if;
>    end loop;
> end FP_Test;
> 


Way to go Wes!  



______________________________________________________________________________ 
Bob Binder                http://www.rbsc.com          RBSC Corporation
312 214-3280  tel         Software Engineering         3 First National Plaza 
312 214-3110  fax         Process Improvement          Suite 1400 
rbinder@rbsc.mapson.com   (remove .mapson to mail)     Chicago, IL 60602-4205





  reply	other threads:[~1997-08-05  0:00 UTC|newest]

Thread overview: 105+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
1997-07-29  0:00 floating point comparison Matthew Heaney
1997-07-30  0:00 ` Robert Dewar
1997-07-30  0:00   ` Matthew Heaney
1997-07-31  0:00     ` Jim Carr
1997-07-30  0:00   ` Matthew Heaney
1997-07-31  0:00     ` Robert Dewar
1997-07-31  0:00     ` Bob Binder  (remove .mapson to email)
1997-07-31  0:00       ` Robert Dewar
1997-08-01  0:00         ` Dale Stanbrough
1997-08-04  0:00         ` Paul Eggert
1997-08-06  0:00           ` Robert Dewar
1997-08-14  0:00             ` Paul Eggert
1997-08-01  0:00       ` user
1997-08-02  0:00         ` Lynn Killingbeck
1997-08-03  0:00           ` Bob Binder  (remove .mapson to email)
1997-08-03  0:00             ` Charles R. Lyttle
1997-08-03  0:00           ` Robert Dewar
1997-08-02  0:00         ` Peter L. Montgomery
1997-08-04  0:00           ` W. Wesley Groleau x4923
1997-08-05  0:00             ` Bob Binder  (remove .mapson to email) [this message]
1997-07-31  0:00     ` Martin Tom Brown
1997-07-31  0:00     ` Samuel Mize
1997-08-02  0:00     ` Lynn Killingbeck
1997-07-31  0:00   ` Gerald Kasner
1997-07-31  0:00     ` Robert Dewar
1997-07-30  0:00 ` Jan Galkowski
1997-07-31  0:00   ` Don Taylor
1997-07-31  0:00     ` Russ Lyttle
1997-08-01  0:00       ` W. Wesley Groleau x4923
1997-08-02  0:00         ` Robert Dewar
1997-08-02  0:00           ` Matthew Heaney
1997-08-03  0:00             ` Robert Dewar
1997-08-04  0:00           ` W. Wesley Groleau x4923
1997-08-05  0:00             ` Jan-Christoph Puchta
1997-08-05  0:00               ` W. Wesley Groleau x4923
1997-08-05  0:00                 ` Samuel Mize
1997-08-06  0:00                 ` Robert Dewar
1997-08-07  0:00                   ` Shmuel (Seymour J.) Metz
1997-08-08  0:00                     ` Peter Shenkin
1997-08-09  0:00                       ` Albert Y.C. Lai
1997-08-06  0:00                 ` Chris L. Kuszmaul
1997-08-07  0:00                   ` Dave Sparks
1997-08-08  0:00                     ` Jan-Christoph Puchta
1997-08-09  0:00                       ` Robert Dewar
1997-08-10  0:00                       ` Lynn Killingbeck
1997-08-08  0:00                     ` Mark Eichin
1997-08-08  0:00                     ` Robert Dewar
     [not found]                   ` <5sbb90$qsc@redtail.cruzio.com>
     [not found]                     ` <5scugs$jdc$1@cnn.nas.nasa.gov>
1997-08-07  0:00                       ` Robert Dewar
1997-08-08  0:00                     ` Gerhard Heinzel
1997-08-08  0:00                       ` Daniel Villeneuve
1997-08-08  0:00                       ` schlafly
1997-08-09  0:00                       ` Robert Dewar
1997-08-09  0:00                         ` David Ullrich
1997-08-10  0:00                           ` Robert Dewar
1997-08-16  0:00                             ` Andrew V. Nesterov
1997-08-18  0:00                               ` Robert Dewar
1997-08-19  0:00                                 ` Hans Olsson
1997-08-19  0:00                                 ` Jim Carr
1997-08-21  0:00                                   ` Christian Bau
1997-08-21  0:00                                     ` Jim Carr
1997-08-21  0:00                                       ` Robert Dewar
1997-08-22  0:00                                         ` Jim Carr
1997-08-22  0:00                                           ` Robert Dewar
1997-08-23  0:00                                             ` Jim Carr
1997-08-24  0:00                                               ` Robert Dewar
     [not found]                                                 ` <5u4eq6$30b$1@news.lth.se>
1997-08-29  0:00                                                   ` Robert Dewar
1997-09-01  0:00                                                     ` Chris RL Morgan
1997-08-29  0:00                                                 ` Andrew V. Nesterov
1997-08-29  0:00                                                   ` Robert Dewar
     [not found]                                                     ` <340DF1DD.2736@iop.com>
1997-09-07  0:00                                                       ` Get_Immediate Robert Dewar
1997-09-07  0:00                                                       ` Get_Immediate Robert Dewar
1997-09-08  0:00                                                       ` Get_Immediate J Giffen
1997-09-01  0:00                                                 ` floating point comparison Jim Carr
     [not found]                                                   ` <checkerEFx6xI.FCM@netcom.com>
1997-09-03  0:00                                                     ` Chris L. Kuszmaul
1997-09-05  0:00                                                       ` Malome Khomo
1997-09-07  0:00                                                       ` Robert Dewar
1997-09-05  0:00                                                   ` Robert Dewar
1997-09-10  0:00                                                     ` Jim Carr
1997-09-12  0:00                                                       ` Robert Dewar
1997-09-15  0:00                                                         ` James Pauley
1997-09-16  0:00                                                           ` Robert Dewar
1997-08-23  0:00                                         ` W. Wesley Groleau x4923
1997-08-23  0:00                                           ` Robert Dewar
1997-08-30  0:00                                 ` Paul Eggert
1997-08-06  0:00             ` Robert Dewar
1997-08-07  0:00               ` Dr. Rex A. Dwyer
     [not found]               ` <33E8DFF6.6F44@pseserv3.fw.hac.com>
1997-08-07  0:00                 ` Robert Dewar
     [not found]                 ` <33EA1251.3466@link.com>
     [not found]                   ` <33EA46CC.226@pseserv3.fw.hac.com>
1997-08-08  0:00                     ` Christian Bau
1997-08-12  0:00                     ` Martin Tom Brown
1997-08-23  0:00                       ` W. Wesley Groleau x4923
1997-08-23  0:00                         ` Robert Dewar
1997-09-05  0:00                         ` Robert I. Eachus
1997-09-06  0:00                           ` schlafly
1997-09-09  0:00                             ` Robert Dewar
1997-09-07  0:00                           ` M. J. Saltzman
1997-09-11  0:00                           ` Robin Rosenberg
1997-08-06  0:00             ` Robert Dewar
     [not found]               ` <33E8E3E1.17EA@pseserv3.fw.hac.com>
     [not found]                 ` <5sbgpk$q0n$1@goanna.cs.rmit.edu.au>
1997-08-07  0:00                   ` Robert Dewar
     [not found]                     ` <33FE4603.1B6B@pseserv3.fw.hac.com>
1997-08-23  0:00                       ` Robert Dewar
1997-08-08  0:00                   ` W. Wesley Groleau x4923
1997-08-07  0:00             ` Do-While Jones
1997-08-03  0:00         ` Brian Rogoff
1997-08-03  0:00           ` Robert Dewar
1997-08-02  0:00 ` Michael Sierchio
1997-08-08  0:00 ` floating point conversions Mark Lusti
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