From owner-freebsd-wireless@FreeBSD.ORG  Thu Dec  1 00:02:43 2011
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Date: Thu, 1 Dec 2011 00:02:43 +0000
From: Alexander Best <arundel@freebsd.org>
To: Igor Mozolevsky <mozolevsky@gmail.com>
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Cc: freebsd-wireless@freebsd.org
Subject: Re: comparing floating points via "==" or "!="
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On Wed Nov 30 11, Igor Mozolevsky wrote:
> On 30 November 2011 22:44, Alexander Best <arundel@freebsd.org> wrote:
> 
> > i played a bit with the gcc -Wfloat-equal warning and noticed that inside
> > sys/dev/ath/ath_rate/sample/tx_schedules.h, a lot of comparisons of floating
> > points are happening ("=="). is there a better way to deal with this?
> 
> as opposed to (abs(a-b) < tolerance)?

fabs(3) actually, or some other way, e.g. described in:

http://www.cygnus-software.com/papers/comparingfloats/comparingfloats.htm

cheers.
alex

> 
> 
> Cheers,
> 
> --
> Igor :-)