From: Geert Bosch <geert@gonzo.sun3.iaf.nl>
Subject: Re: fixed point vs floating point
Date: 1997/11/23
Date: 1997-11-23T00:00:00+00:00 [thread overview]
Message-ID: <65846t$4vq$1@gonzo.sun3.iaf.nl> (raw)
In-Reply-To: mheaney-ya023680002211970739180001@news.ni.net
Matthew Heaney <mheaney@ni.net> wrote:
Anyway, I'll accept that fixed point operations are slower, but the
question remains: Why do most programmers insist on using floating point
when a fixed point better models the abstraction? Is the reason solely
based on efficiency?
By the way, are there off-the-shelf subprograms (in Ada preferably, but I'd
take any language) for computing the elementary functions (sin, cos, etc)
of a fixed point angle?
Maybe your second questions answers the first. It is really useless to
try hard to calculate a sinus using integer arithmetic when you have a
perfectly fine and very fast, well tested floating-point unit in your
computer that can calculate the sinus with a delta smaller than
0.000000000000001 probably.
Converting a fixed point value to fpt, issue the sinus instruction
and convert it back is much faster than even thinking about doing it in
fixed point. ;-)
Regards,
Geert
next prev parent reply other threads:[~1997-11-23 0:00 UTC|newest]
Thread overview: 64+ messages / expand[flat|nested] mbox.gz Atom feed top
1997-11-22 0:00 fixed point vs floating point Matthew Heaney
1997-11-22 0:00 ` Tucker Taft
1997-11-22 0:00 ` Robert Dewar
1997-11-22 0:00 ` Matthew Heaney
1997-11-23 0:00 ` Geert Bosch [this message]
1997-11-23 0:00 ` Tom Moran
1997-11-25 0:00 ` John A. Limpert
1997-11-25 0:00 ` Robert Dewar
1997-11-25 0:00 ` Robert Dewar
1997-11-23 0:00 ` Matthew Heaney
1997-11-23 0:00 ` Robert Dewar
1997-11-24 0:00 ` Herman Rubin
1997-11-24 0:00 ` Robert Dewar
1997-11-25 0:00 ` Joe Gwinn
1997-11-25 0:00 ` Robert Dewar
1997-11-25 0:00 ` Joe Gwinn
1997-11-25 0:00 ` Robert Dewar
1997-11-26 0:00 ` Joe Gwinn
1997-11-26 0:00 ` Robert Dewar
1997-12-01 0:00 ` Joe Gwinn
1997-12-01 0:00 ` Robert Dewar
1997-12-01 0:00 ` Joe Gwinn
1997-12-03 0:00 ` robin
1997-11-25 0:00 ` Matthew Heaney
1997-11-26 0:00 ` William A Whitaker
1997-11-24 0:00 ` Geert Bosch
1997-11-24 0:00 ` Vince Del Vecchio
1997-11-24 0:00 ` Vince Del Vecchio
1997-12-03 0:00 ` robin
-- strict thread matches above, loose matches on Subject: below --
2011-09-29 10:25 RasikaSrinivasan@gmail.com
2011-09-29 10:49 ` AdaMagica
2011-09-29 13:38 ` Martin
2011-09-30 10:17 ` Stephen Leake
2011-09-30 16:25 ` tmoran
2011-09-30 16:52 ` Dmitry A. Kazakov
2011-10-01 11:09 ` Stephen Leake
2011-09-30 19:26 ` tmoran
2011-09-30 22:31 ` tmoran
2011-10-01 13:37 ` RasikaSrinivasan@gmail.com
2011-10-02 14:19 ` Stephen Leake
1997-12-02 0:00 Robert Dewar
1997-12-02 0:00 ` Joe Gwinn
1997-12-02 0:00 ` Ken Garlington
1997-12-03 0:00 ` Joe Gwinn
1997-12-04 0:00 ` Robert Dewar
1997-12-04 0:00 ` Shmuel (Seymour J.) Metz
1997-12-02 0:00 ` Robert Dewar
1997-12-02 0:00 ` Matthew Heaney
1997-12-03 0:00 ` Robert Dewar
1997-12-03 0:00 ` robin
1997-12-03 0:00 ` Robert Dewar
1997-12-03 0:00 ` Shmuel (Seymour J.) Metz
1997-12-03 0:00 ` Robert Dewar
1997-12-03 0:00 ` Matthew Heaney
1997-12-04 0:00 ` Shmuel (Seymour J.) Metz
1997-12-04 0:00 ` Robert Dewar
1997-12-03 0:00 ` Robert Dewar
1997-12-03 0:00 ` robin
1997-11-28 0:00 tmoran
1997-11-28 0:00 ` Robert Dewar
1997-11-27 0:00 tmoran
1997-11-27 0:00 ` Robert Dewar
1997-11-29 0:00 ` Tarjei T. Jensen
[not found] <9711221603.AA03295@nile.gnat.com>
1997-11-22 0:00 ` Ken Garlington
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