From: Stuart Palin <stuart.palin@gecm.com>
Subject: Re: Can compilers do this?
Date: 1996/02/23
Date: 1996-02-23T00:00:00+00:00 [thread overview]
Message-ID: <4gkfs2$h19@gcsin3.geccs.gecm.com> (raw)
In-Reply-To: 4gjd6g$mfq@newsbf02.news.aol.com
bwburnsed@aol.com (BWBurnsed) wrote:
[snip]
>
>Repeatedly in this code (in many files), there are places where a floating
>point variable is tested to see if it is negative. However, the way it is
>done is:
>
> if X * abs(X) < 0.0 then ...
>
>Is there (or was there ever) some pathological anomaly about floating
>point
>implementations that would make a conversion (abs) and floating point
>multiply
A quick guess on this is a concern over negative zero in the IEEE
standard for FP numbers, though using abs and * seems overkill since
I would have thought if (X <> 0.0) and then (X < 0.0) might have been
better.
Stuart Palin
stuart.palin@gecm.com
next prev parent reply other threads:[~1996-02-23 0:00 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
1996-02-22 0:00 Can compilers do this? BWBurnsed
1996-02-23 0:00 ` Cordes MJ
1996-02-23 0:00 ` Robert Dewar
1996-02-23 0:00 ` Stuart Palin [this message]
1996-02-23 0:00 ` Mark A Biggar
1996-02-24 0:00 ` Robert A Duff
1996-02-23 0:00 ` Robert Dewar
1996-02-25 0:00 ` Robert Dewar
1996-02-23 0:00 ` Robert Dewar
1996-02-26 0:00 ` Robert I. Eachus
1996-02-26 0:00 ` BWBurnsed
-- strict thread matches above, loose matches on Subject: below --
1996-02-26 0:00 Marin David Condic, 407.796.8997, M/S 731-93
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