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From: dewar@merv.cs.nyu.edu (Robert Dewar)
Subject: Re: floating point comparison
Date: 1997/07/31
Date: 1997-07-31T00:00:00+00:00	[thread overview]
Message-ID: <dewar.870386556@merv> (raw)
In-Reply-To: 01bc9dca$762b6000$e1e989cc@gort


Bob Binder says

<<I haven't followed the IEEE fp standard, but I can't imagine how
(without resorting to some kind of BCD representation) any floating
point scheme using a non-decimal radix gets around the fundamental fact
that there are non-terminal fractions in this radix which are not
point scheme using a non-decimal radix gets around the fundamental fact
that there are non-terminal fractions in this radix which are not
non-terminal in a decimal radix.
>>

There is nothing to "get around" here. The IEEE floating-point standard
is a well defined arithmetic system, with a well defined set of values
with well defined operations on them.

It is NOT, and never pretends to be, a representation of real arithmetic.
It has its own laws and axioms, but they are of course different from
those of real arithmetic.

There is nothing special about decimal arithmetic here. The laws of
physics are not made up by a deity with ten fingers. Real arithmetic
is of course independent of the chosen base, but so are observations
in the physical world. 

The IEEE fpt standard (IEEE-854) provides binary and decimal variations.
It is of course the binary version that is used on most modern
computers.






  reply	other threads:[~1997-07-31  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     ` Robert Dewar
1997-07-31  0:00     ` Samuel Mize
1997-07-31  0:00     ` Bob Binder  (remove .mapson to email)
1997-07-31  0:00       ` Robert Dewar [this message]
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)
1997-07-31  0:00     ` Martin Tom Brown
1997-08-02  0:00     ` Lynn Killingbeck
1997-07-30  0:00   ` Matthew Heaney
1997-07-31  0:00     ` Jim Carr
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                     ` Robert Dewar
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
     [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                       ` schlafly
1997-08-08  0:00                       ` Daniel Villeneuve
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
     [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
1997-08-07  0:00               ` Dr. Rex A. Dwyer
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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