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From: Kevin Ryde <user42@zip.com.au>
To: guile-devel@gnu.org
Subject: Re: asserting the equality of double values
Date: Tue, 18 Sep 2007 10:13:32 +1000	[thread overview]
Message-ID: <87k5qoal03.fsf@blah.blah> (raw)
In-Reply-To: <CMM.0.95.0.1189884022.beebe@psi.math.utah.edu> (Nelson H. F. Beebe's message of "Sat, 15 Sep 2007 13:20:22 -0600 (MDT)")

"Nelson H. F. Beebe" <beebe@math.utah.edu> writes:
>
> Subtracting one produces a significant of all
> 1-bits:  2**53 - 1 = +0x1.fffffffffffffp+52,

Yes.

> and that is the
> next-to-largest exactly representable whole number in this arithmetic
> system.  Its floor is identical, so "x == floor()" is true.

Well, it's supposed to be.  I think I put in that test.  If it's failing
on alpha someone will want to dig around and see how it went wrong.  It
ought to be pretty simple, all the values are integers, so no rounding
at all (and it hasn't even reached the actual scm_c_round).


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  reply	other threads:[~2007-09-18  0:13 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-09-15 17:53 asserting the equality of double values Kamaraju S Kusumanchi
2007-09-15 19:20 ` Nelson H. F. Beebe
2007-09-18  0:13   ` Kevin Ryde [this message]
2007-09-18  2:44     ` Kamaraju S Kusumanchi
2007-09-17 17:45 ` Stephen Compall
2007-09-18  2:45   ` Kamaraju S Kusumanchi

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