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Date: Sat, 18 Oct 1997 13:58:54 +1000
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199710180358.NAA08402@godzilla.zeta.org.au>
To: bugs@FreeBSD.ORG, mike@NetworX.ie
Subject: Re: Rounding up is -odd-
Sender: owner-freebsd-bugs@FreeBSD.ORG
X-Loop: FreeBSD.org
Precedence: bulk

>Why does
>	printf "%1.2f\n" 7.005
>produce
>	7.00
>while
>	printf "%1.2f\n" 8.005
>produces
>	8.01
>?

For the same reason that
	printf "%1.20f\n" 7.005
produces
	7.00499999999999989342
and
	printf "%1.20f\n" 8.005
produces
	8.00500000000000078160

(double)7.005 isn't actually 7.005, since doubles have a finite amount
of precision and 7.005 is not exactly representable.

Bruce