From mboxrd@z Thu Jan 1 00:00:00 1970 Path: main.gmane.org!not-for-mail From: Kevin Ryde Newsgroups: gmane.lisp.guile.devel Subject: Re: Nearly finished (re)integrating GMP for bignums. Date: Thu, 13 Feb 2003 09:00:47 +1000 Sender: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Message-ID: <87y94lcdeo.fsf@zip.com.au> References: <87heb9pjni.fsf@raven.i.defaultvalue.org> <87r8adihxe.fsf@zagadka.ping.de> NNTP-Posting-Host: main.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: main.gmane.org 1045091353 20058 80.91.224.249 (12 Feb 2003 23:09:13 GMT) X-Complaints-To: usenet@main.gmane.org NNTP-Posting-Date: Wed, 12 Feb 2003 23:09:13 +0000 (UTC) Return-path: Original-Received: from monty-python.gnu.org ([199.232.76.173]) by main.gmane.org with esmtp (Exim 3.35 #1 (Debian)) id 18j5rY-0004ML-00 for ; Thu, 13 Feb 2003 00:00:21 +0100 Original-Received: from localhost ([127.0.0.1] helo=monty-python.gnu.org) by monty-python.gnu.org with esmtp (Exim 4.10.13) id 18j5sx-0007J3-07 for guile-devel@m.gmane.org; Wed, 12 Feb 2003 18:01:47 -0500 Original-Received: from list by monty-python.gnu.org with tmda-scanned (Exim 4.10.13) id 18j5sf-0007CM-00 for guile-devel@gnu.org; Wed, 12 Feb 2003 18:01:29 -0500 Original-Received: from mail by monty-python.gnu.org with spam-scanned (Exim 4.10.13) id 18j5sc-00077R-00 for guile-devel@gnu.org; Wed, 12 Feb 2003 18:01:28 -0500 Original-Received: from sunny.pacific.net.au ([203.2.228.40]) by monty-python.gnu.org with esmtp (Exim 4.10.13) id 18j5sb-000716-00 for guile-devel@gnu.org; Wed, 12 Feb 2003 18:01:25 -0500 Original-Received: from wisma.pacific.net.au (wisma.pacific.net.au [210.23.129.72]) by sunny.pacific.net.au with ESMTP id h1CN1KMr020566 for ; Thu, 13 Feb 2003 10:01:20 +1100 (EST) Original-Received: from localhost (ppp88.dyn228.pacific.net.au [203.143.228.88]) by wisma.pacific.net.au with ESMTP id KAA06124 for ; Thu, 13 Feb 2003 10:01:18 +1100 (EST) Original-Received: from gg by localhost with local (Exim 3.35 #1 (Debian)) id 18j5s0-0000er-00; Thu, 13 Feb 2003 09:00:48 +1000 Original-To: guile-devel@gnu.org In-Reply-To: (Mikael Djurfeldt's message of "Wed, 12 Feb 2003 18:34:59 +0100") User-Agent: Gnus/5.090013 (Oort Gnus v0.13) Emacs/21.2 (i386-pc-linux-gnu) X-BeenThere: guile-devel@gnu.org X-Mailman-Version: 2.1b5 Precedence: list List-Id: Developers list for Guile, the GNU extensibility library List-Help: List-Post: List-Subscribe: , List-Archive: List-Unsubscribe: , Errors-To: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Xref: main.gmane.org gmane.lisp.guile.devel:1925 X-Report-Spam: http://spam.gmane.org/gmane.lisp.guile.devel:1925 Mikael Djurfeldt writes: > > 2. What do you mean by a "good" RNG? I'd say it is good if it is > fast. In gmp we're looking at a Blum-Blum-Shub algorithm for possible inclusion, it's based on cryptographic principles, and so supposedly suits such applications (which are rather specialized of course). > Our generator is fast. Can you name any single other > criterion which is not "religious" and which our generator doesn't > fulfil? (I'm talking about something measurable here.) For reference, the next gmp will be have a Mersenne Twister generator contributed by Pedro Gimeno, and it'll be the default too (gmp_randinit_default). It's fast, and very random according to those who pay attention to such things (I'm no expert). Rob Browning writes: > > I wonder how fast the GMP RNGs are (I currently have no idea). The current linear congruential generator isn't as good as it could be, it uses bignum operations even for the common case of a modulus that fits in one or two machine words. Mersenne Twister ought to end up being as fast or faster than L-C, and the lack of randomness of L-C is well-known, so there oughtn't be any direct call for the latter any more, not except maybe for special purposes like experimenting with very un-random sequences. _______________________________________________ Guile-devel mailing list Guile-devel@gnu.org http://mail.gnu.org/mailman/listinfo/guile-devel