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From: Stuart Palin <stuart.palin@gecm.com>
Subject: Re: Can compilers do this?
Date: 1996/02/23
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Date: 1996-02-23T00:00:00+00:00
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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