From: John Darrington <john@darrington.wattle.id.au>
To: Noah Lavine <noah.b.lavine@gmail.com>
Cc: Guile Mailing List <guile-user@gnu.org>
Subject: Re: Can somebody help to explain why result from atan does not equal a real?
Date: Thu, 31 Jan 2013 15:50:17 +0100 [thread overview]
Message-ID: <20130131145017.GA27085@jocasta.intra> (raw)
In-Reply-To: <CA+U71=MEU3sU_RZKqXW8xjKdtHX=HxMWsm-8UXb-qUcHeCgMeQ@mail.gmail.com>
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On Thu, Jan 31, 2013 at 08:32:53AM -0500, Noah Lavine wrote:
What you have here is a precision problem.
scheme@(guile-user)> (= 3.14159265358979 (atan 0 -1))
$8 = #f
scheme@(guile-user)> (= $7 (atan 0 -1))
$9 = #t
It might be possible to have Guile print more digits and make this problem
go away.
Noah Lavine
pi is an irrational number. You would need an infinite number of digits wouldn't you?
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next prev parent reply other threads:[~2013-01-31 14:50 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-01-31 10:50 Can somebody help to explain why result from atan does not equal a real? Hengqing Hu
2013-01-31 13:32 ` Noah Lavine
2013-01-31 14:50 ` John Darrington [this message]
2013-01-31 14:52 ` Noah Lavine
2013-01-31 23:51 ` Mark H Weaver
2013-02-01 0:30 ` Mark H Weaver
2013-02-01 9:10 ` Mark H Weaver
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