From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (from majordomo@localhost) by pauillac.inria.fr (8.7.6/8.7.3) id TAA29862; Mon, 27 May 2002 19:40:44 +0200 (MET DST) X-Authentication-Warning: pauillac.inria.fr: majordomo set sender to owner-caml-list@pauillac.inria.fr using -f Received: from nez-perce.inria.fr (nez-perce.inria.fr [192.93.2.78]) by pauillac.inria.fr (8.7.6/8.7.3) with ESMTP id TAA30361 for ; Mon, 27 May 2002 19:40:43 +0200 (MET DST) Received: from tw304h3.cpmc.columbia.edu (tw304h3.cpmc.columbia.edu [156.111.84.180]) by nez-perce.inria.fr (8.11.1/8.11.1) with ESMTP id g4RHegr11573 for ; Mon, 27 May 2002 19:40:43 +0200 (MET DST) Received: from trott by tw304h3.cpmc.columbia.edu with local (Exim 3.35 #1 (Debian)) id 17COWP-0005gh-00 for ; Mon, 27 May 2002 13:43:05 -0400 Content-Type: text/plain; charset="iso-8859-1" From: Oleg To: caml-list@pauillac.inria.fr Subject: Re: [Caml-list] inversion de matrice en caml Date: Mon, 27 May 2002 13:43:05 -0400 X-Mailer: KMail [version 1.3.2] References: In-Reply-To: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Message-Id: Sender: owner-caml-list@pauillac.inria.fr Precedence: bulk On Monday 27 May 2002 10:06 am, thomas Icart wrote: > Je suis en math-spe .Pour mon tipe sur la geometrie des nombres ,j'aurai > besoin d'un programme qui puisse m'inverser des matrices de taille au > moins 15*15 dans un temps assez raisonnable. > Je vous remercie d'avance. > Thomas ICART. > Typically, responsible programmers will use LAPACK ( http://www.netlib.org/lapack/lug/lapack_lug.html ) for all their linear algebra needs. LAPACK in turn uses BLAS (http://www.netlib.org/blas/). If speed is important to you, and your hardware vendor does not supply hardware-specific BLAS, consider a self-optimizing version of BLAS called ATLAS ( http://math-atlas.sourceforge.net/ ). Up to 10x speed-ups are possible with ATLAS compared to generic BLAS. If you don't want to "roll your own" interface to LAPACK (as it is in FORTRAN), consider LACAML (found at http://www.ai.univie.ac.at/~markus/home/ocaml_sources.html ). I haven't tried it yet. BTW, in most cases matrix inversion is not required. To solve A*X=B (where X is either a vector or a matrix) use xGESV subroutine (x = C,Z,S,D - denotes complex, double complex, float, double respectively). If you insist on finding the inverse, use xGETRI. HTH Oleg ------------------- To unsubscribe, mail caml-list-request@inria.fr Archives: http://caml.inria.fr Bug reports: http://caml.inria.fr/bin/caml-bugs FAQ: http://caml.inria.fr/FAQ/ Beginner's list: http://groups.yahoo.com/group/ocaml_beginners