From owner-sc22wg5@open-std.org Wed Feb 10 19:58:45 2010 Return-Path: X-Original-To: sc22wg5-dom8 Delivered-To: sc22wg5-dom8@www2.open-std.org Received: by www2.open-std.org (Postfix, from userid 521) id E7AD2C178DC; Wed, 10 Feb 2010 19:58:45 +0100 (CET) X-Original-To: sc22wg5@open-std.org Delivered-To: sc22wg5@open-std.org Received: from mail1.cray.com (mail1.cray.com [136.162.62.100]) by www2.open-std.org (Postfix) with ESMTP id 2A930C178DA for ; Wed, 10 Feb 2010 19:58:44 +0100 (CET) Received: from beaver.us.cray.com (beaver.us.cray.com [172.30.74.51]) by mail1.cray.com (8.13.6/8.13.3/gw-5323) with ESMTP id o1AIp8S5000086 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=FAIL); Wed, 10 Feb 2010 12:51:09 -0600 (CST) Received: from cfexcas01.americas.cray.com (cfexcas01-2.us.cray.com [172.30.74.227]) by beaver.us.cray.com (8.13.8/8.13.3/hub-5273) with ESMTP id o1AIp5d2001169; Wed, 10 Feb 2010 12:51:05 -0600 Received: from fortran.us.cray.com (172.31.19.200) by cfexcas01.americas.cray.com (172.30.74.226) with Microsoft SMTP Server (TLS) id 8.1.393.1; Wed, 10 Feb 2010 12:51:04 -0600 Message-ID: <4B73001A.8010407@cray.com> Date: Wed, 10 Feb 2010 12:51:06 -0600 From: Bill Long Reply-To: Organization: Cray Inc. User-Agent: Thunderbird 2.0.0.23 (Macintosh/20090812) MIME-Version: 1.0 To: "N.M. Maclaren" Cc: "John.Reid@stfc.ac.uk" , fortran standards email list for J3 , WG5 Subject: Re: [ukfortran] (SC22WG5.4170) (j3.2006) Urgent: letter ballot on interps References: <20100201122928.54FB8C178E4@www2.open-std.org> <20100210005356.4ABF5C3BA23@www2.open-std.org> In-Reply-To: Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit X-Cray-VirusStatus: clean Sender: owner-sc22wg5@open-std.org Precedence: bulk N.M. Maclaren wrote: > On Feb 10 2010, Bill Long wrote: >> Comment for F03/0039 - HYPOT() >> >> Nick's comments about the IEEE nonconformance of the proposed change >> might be considered for 13.7.69 "HYPOT (X, Y)" in F08 >> 09-007r3[353:18-27]. The HYPOT defined in Note 14.7 is not really >> claimed to be the official IEEE HYPOT, but rather is a contrivance to >> illustrate the setting and getting of IEEE flags. > > Ah! That confused me. > >> would result in a NaN result. It might also make Fred Tydeman happier >> if the Note pointed out that the example is not an implementation of >> the IEEE HYPOT function (at least it's not a valid one). I believe >> that Fred (and maybe Nick) would be happy of the name of the function >> were something other than HYPOT, to avoid confusion with the IEEE >> HYPOT function. > > It would assuredly be less confusing. The potential for confusion is greater in F08. In the context of the F03 standard (against which the interp is formally filed), one could argue that only "experts" who knew about HYPOT from elsewhere would be confused. In F08 we actually have an intrinsic function with this name and the same argument list. The temptation to assume the Note is referring to the same function as the one specified in Clause 13 seems quite high to me. Cheers, Bill > > On the F2008 point, I don't approve of IEEE's inconsistent approach to > NaNs, but this is one of the less problematic cases, and there needs to > be very strong reason to be incompatible with its explicit wording. > > Regards, > Nick. > > -- Bill Long longb@cray.com Fortran Technical Support & voice: 651-605-9024 Bioinformatics Software Development fax: 651-605-9142 Cray Inc./Cray Plaza, Suite 210/380 Jackson St./St. Paul, MN 55101