From: Mark H Weaver <mhw@netris.org>
To: "Tommi Höynälänmaa" <tommi.hoynalanmaa@gmail.com>
Cc: guile-devel@gnu.org
Subject: Re: Is there something wrong with complex atan in guile?
Date: Wed, 22 Jul 2015 18:42:15 -0400 [thread overview]
Message-ID: <87a8unzuew.fsf@netris.org> (raw)
In-Reply-To: <CAAkPRiwAzQHHU79hM8p9LtRj=6orQs682coj28NNOuwtAgC=wg@mail.gmail.com> ("Tommi \=\?utf-8\?B\?SMO2eW7DpGzDpG5tYWEiJ3M\=\?\= message of "Wed, 22 Jul 2015 14:07:31 +0300")
Tommi Höynälänmaa <tommi.hoynalanmaa@gmail.com> writes:
> I get the following results with guile 2.0.9:
>
> ---cut here---
> scheme@(guile-user)> (atan (tan -0.5+2.0i))
> $1 = 1.070796326794897+1.9999999999999996i
> scheme@(guile-user)> (tan (atan -0.5+2.0i))
> $2 = 0.1176470588235294+0.4705882352941177i
> ---cut here---
>
> Although there are multiple branches in the complex atan function the
> previous results do not seem correct. Is there something wrong here.
You're right, our atan procedure was broken in commit
ad79736c68a803a59814fbfc0cb4b092c2b4cddf. I will fix it before the
2.0.12 release, and review the other changes made in that commit.
Mark
next prev parent reply other threads:[~2015-07-22 22:42 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-07-22 11:07 Is there something wrong with complex atan in guile? Tommi Höynälänmaa
2015-07-22 22:42 ` Mark H Weaver [this message]
2015-07-23 1:04 ` Mark H Weaver
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