From owner-freebsd-chat Wed Oct 21 11:25:16 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id LAA19853 for freebsd-chat-outgoing; Wed, 21 Oct 1998 11:25:16 -0700 (PDT) (envelope-from owner-freebsd-chat@FreeBSD.ORG) Received: from dingo.cdrom.com (dingo.cdrom.com [204.216.28.145]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id LAA19840; Wed, 21 Oct 1998 11:25:12 -0700 (PDT) (envelope-from mike@dingo.cdrom.com) Received: from dingo.cdrom.com (localhost.cdrom.com [127.0.0.1]) by dingo.cdrom.com (8.9.1/8.8.8) with ESMTP id LAA01093; Wed, 21 Oct 1998 11:28:21 -0700 (PDT) (envelope-from mike@dingo.cdrom.com) Message-Id: <199810211828.LAA01093@dingo.cdrom.com> X-Mailer: exmh version 2.0.2 2/24/98 To: Bruce Evans cc: jobaldwi@vt.edu, mike@smith.net.au, bde@FreeBSD.ORG, freebsd-chat@FreeBSD.ORG Subject: Re: Bug in rintf()?... In-reply-to: Your message of "Thu, 22 Oct 1998 04:11:58 +1000." <199810211811.EAA32442@godzilla.zeta.org.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Wed, 21 Oct 1998 11:28:21 -0700 From: Mike Smith Sender: owner-freebsd-chat@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > >> I've been having a problem with rintf() not rounding properly, and I don't > >> understand the code in /usr/src/libm/common_source/floor.c well enough to > >> figure out where it is going wrong. Here is the problem I'm having though: > > > >We actually use the Sun-supplied math library, so you should be looking > >at src/lib/msun/src/s_rintf.c > > > >> rintf(3.5) returns 4.0 > >> rintf(3910.5) returns 3910.0 (should return 3911.0) > > This seems to be correct. rintf() rounds to the nearest integer according > to the prevailing rounding mode. The default prevailing rounding mode > is round-to-even. rintf() even seems to get this right for all the > other rounding modes (towards +Inf, towards -Inf and towards 0). Where do you set the rounding mode? The only reference I could find was fpsetround(), which offers nearest, -inf, +inf and truncate. math(3) lists 3 types for ieee754 (+inf, -inf and 0). -- \\ Sometimes you're ahead, \\ Mike Smith \\ sometimes you're behind. \\ mike@smith.net.au \\ The race is long, and in the \\ msmith@freebsd.org \\ end it's only with yourself. \\ msmith@cdrom.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-chat" in the body of the message