From owner-freebsd-arch Mon Feb 26 0: 3:35 2001 Delivered-To: freebsd-arch@freebsd.org Received: from peach.ocn.ne.jp (peach.ocn.ne.jp [210.145.254.87]) by hub.freebsd.org (Postfix) with ESMTP id AF3B237B4EC for ; Mon, 26 Feb 2001 00:03:32 -0800 (PST) (envelope-from dcs@newsguy.com) Received: from newsguy.com (p47-dn02kiryunisiki.gunma.ocn.ne.jp [211.0.245.112]) by peach.ocn.ne.jp (8.9.1a/OCN/) with ESMTP id RAA26234; Mon, 26 Feb 2001 17:03:22 +0900 (JST) Message-ID: <3A9A0D1F.BEC3ECA2@newsguy.com> Date: Mon, 26 Feb 2001 17:00:31 +0900 From: "Daniel C. Sobral" X-Mailer: Mozilla 4.7 [en] (Win98; I) X-Accept-Language: en,pt-BR MIME-Version: 1.0 To: Kris Kennaway Cc: Terry Lambert , arch@FreeBSD.ORG Subject: Re: cvs commit: ports/astro/xglobe/files patch-random References: <20010225005813.A29124@mollari.cthul.hu> <200102260241.TAA07028@usr05.primenet.com> <20010225193157.A16118@mollari.cthul.hu> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Kris Kennaway wrote: > > > the algorithm will result in ciphered data becoming inaccesable. > > > > Repeatability of results in montecarlo based physics simulations is > > also an issue. FreeBSD would end up being much less useful for real > > numeric work, should rand() be changed. > > This won't happen because the interface won't change. Huh? I have some Promela protocol simulations here. These simulations, which use huge amounts of memory, are stored in a simple fashion: the key used by rand() and the point at which the LTC conditions were satisfied. Whatever you do to the algorithm, just keep in mind that the sequence of numbers generated from that key must remain the same, or I'll have to throw out all the simulations I have stored. Kind of defeats the purpose of changing the algorithm, don't you think? > > Ignoring that, what makes you think you can come up with a better > > algorithm than Donald Knuth? > > Me? No, but others have done so. Terry, the existing rand() is a bad > algorithm just about any way you look at it. I don't see the rand() algorithm as being bad in any way, unless you stupidly try to use it for security purposes, like generating an encryption key. -- Daniel C. Sobral (8-DCS) dcs@newsguy.com dcs@freebsd.org capo@kzinti.bsdconspiracy.net Acabou o hipismo-arte. Mas a desculpa brasileira mais ouvida em Sydney e' que nao tem mais cavalo bobo por ai'. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message