Send mail to: mgnet@cs.yale.edu for the digests or bakeoff mgnet-requests@cs.yale.edu for comments or help Anonymous ftp repository: www.mgnet.org (128.163.209.19) Current editor: Craig Douglas douglas-craig@cs.yale.edu WWW Sites: http://www.mgnet.org or http://casper.cs.yale.edu/mgnet/www/mgnet.html or http://www.cerfacs.fr/~douglas/mgnet.html or http://phase.hpcc.jp/mirrors/mgnet or http://www.tat.physik.uni-tuebingen.de/~mgnet Today's editor: Craig Douglas (douglas-craig@cs.yale.edu) Volume 12, Number 8 (approximately August 31, 2002) Today's topics: Full MG Code for optimality systems - A. Borzi parallel Algebraic Recursive Multilevel Solver (pARMS) available Pieter Wesseling's Book Images Reading Level MGNet's Conference Page Help in Finding Software Benchmarking elementary functions MAFELAP 2003, 21 - 24 June 2003 (First Announcement) ------------------------------------------------------- Date: Fri, 16 Aug 2002 09:29:24 +0200 From: "Dr. Alfio Borzi"Subject: Full MG Code for optimality systems - A. Borzi I would be very pleased if you would consider the following submission to MGNet Software. I would like to contribute to the MGNet Software with a full multigrid code for optimality systems. As we are experiencing, there is growing interest in fast methods for optimization problems, especially multigrid methods. With the present code, called 'controlla.for' (sorry, I keep choosing italian names), I wish give a contribution to the development of multigrid methods for optimal control problems. I hope that people interested in optimal control problems and wishing to use multigrid methods may benefit from having this code at disposal. Brief description: CONTROLLA.FOR: A full multigrid method for the solution of an optimality system arising from optimal control of the solid fuel ignition model. Optimal control (OPC) problems are receiving increasing attention in the scientific community. As an example of optimal control formulation consider the minimization of the following cost functional J = |U - Z|^2/2 + a*|F|^2/2 where U satisfies -DELTA U = F in a given domain Omega. A way to solve this OPC problem is to reformulate it as an unconstrained minimization problem by introducing the Lagrangian L = J + < -DELTA U - F, P > where P is a Lagrangian multiplier. Derive the necessary conditions for a minimum to obtain: -DELTA U = F -DELTA P = - ( U - Z ) a*F - P = 0 This is called the optimality system. For a partial list of references concerning the use of multigrid for solving optimality systems see Ref. (1) below. The code CONTROLLA.FOR solves the optimality system of the following OPC problem min ( |U - Z|^2/2 + B*|EXP(U)-EXP(Z)|^2/2 + a*|F|^2/2 ) -DELTA U - D*EXP(U) = F This reaction-diffusion model describes explosive chemical reaction. Control is required to drive combustion in a desired way or to avoid explosion. A detailed discussion of this problem and of its multigrid solution is given in (1) Alfio Borzi' and Karl Kunisch, The Numerical Solution of the Steady State Solid Fuel Ignition Model and Its Optimal Control, SIAM J. Sci. Comp., 22(1) (2000), pp. 263-284. In the linear case (B=0,D=0) CONTROLLA.FOR solves the optimality system given above. Convergence results in the framework of local mode analysis and in the framework of the theory given in J.H. Bramble, Do Y. Kwak, and J.E. Pasciak, Uniform convergence of multigrid V-cycle iterations for indefinite and nonsymmetric problems, SIAM J. Numer. Anal. 31 (1994), pp. 1746-1763. are presented in (2) A. Borzi, K. Kunisch, and Do Y. Kwak, Accuracy and Convergence Properties of the Finite Difference Multigrid Solution of an Optimal Control Optimality System, Univ. of Graz & Tech. Univ., SFB F003, Rep. No. 245, July 2002, Graz. To appear in SIAM J. Control Optim.. This code has been developed based on techniques and software given in Achi Brandt, Multi-level adaptive solutions to boundary-value problems, Math. Comp., 31 (1977), pp. 333-390. Achi Brandt, Multi-level adaptive techniques (MLAT) for partial differential equations: Ideas and software, Mathematical Software III, J.R. Rice Ed., Academic Press, New York, 1977, pp. 277-318. CONTROLLA.FOR is a public domain code. I provide the program ``AS IS'' without warranty of any kind. ALFIO BORZI' INSTITUT FÜR MATHEMATIK KARL-FRANZENS-UNIVRSITÄT GRAZ HEINRICHSTR. 36, A-8010 GRAZ AUSTRIA ALFIO.BORZI@UNI-GRAZ.AT ------------------------------------------------------- Date: Fri, 30 Aug 2002 18:51:09 -0500 (CDT) From: Yousef Saad Subject: parallel Algebraic Recursive Multilevel Solver (pARMS) available Dear colleagues: We are pleased to announce the availability of version 0.2 of the parallel Algebraic Recursive Multilevel Solver (pARMS). pARMS is a package for solving large sparse linear systems on parallel computers. It includes a fairly wide variety of preconditioning options: * Additive Schwarz type using ilu0, ilut, iluk, or arms factorization * Schur complement - based techniques using ilu0, ilut, iluk, or arms factorization (left, right versions) * Schur complement-based techniques using global ilu(0) or symmetric GS for the Schur complement Configuration options are available for the IBM SP, the SGI Origin, and a cluster of Linux machines. Visit the pARMS web-site at http://www.cs.umn.edu/~saad/software/pARMS for the software, related articles, and viewgraphs. Main contributors to the project: YS, Zhongze Li, Masha Sosonkina, Brian Suchomel, Devdatta Kulkarni, Yu Liang. Acknowledgments: work supported by NSF/ACI PS: For those interested - a sequential versionof ARMS in matlab is available in the matlab demos of a recent tutorial: http://www-users.cs.umn.edu/~saad/Brisbane/home.html Yousef Saad saad@cs.umn.edu Dept of computer Science & Eng. http://www.cs.umn.edu/~saad University of Minnesota ph: (612) 624 7804 200 Union st. SE. fax: (612) 625 0572 Minneapolis, MN 55155 ------------------------------------------------------- Date: Fri, 16 Aug 2002 20:28:51 +0200 (CEST) From: Christian Cornelssen Subject: Pieter Wesseling's Book Images Dear Mr Douglas, I have downloaded the Wesseling book image files placed at http://www.mgnet.org/mgnet-books-wesseling.html When preparing the PDFs for printing, I found the following: * The Webpage lists the page range for chapter 5 as 60-94. This should be 60-78. * preface.pdf: Some left text flows off the second (print) page. (Anyway, I don't need it.) * ch8.pdf: As you mentioned, pages 194,195 pose problems. They should be merged onto one print page. Currently, they are separate and each on the wrong side (left<>right). I have attached a file `p194+195.pdf' that has these pages merged as desired (by using some Ghostscript tools and PS utilities). * index.pdf: The last page is on the wrong side (should be left). I have attached a file `p284.pdf' containing the image justified as indicated above. To approximately center the PDFs on A4 paper, I recommend displacing the typearea about 6pt rightwards and 8pt downwards. For letter paper, shifting 14pt rightwards and 33pt downwards should give fine results. These measures apply to the non-rotated (i.e. portrait-oriented) files. I haven't centered the attached PDFs. If you are interested in details on how to center the PDFs for printing, I can provide further information. Best regards, Christian Cornelssen Editor's Note: The book has been updated with the better scans. ------------- ------------------------------------------------------- Date: Tue, 6 Aug 2002 22:59:38 -0600 (MDT) From: Jan Mandel Subject: Reading Level Look at http://www.amazon.com/exec/obidos/ASIN/0198536062/qid=1028696183/sr=1-30/ref=sr_1_30/103-8782815-9300662 "reading level" Editor's Note: This is an amazingly well written book to get this rating. ------------- ------------------------------------------------------- Date: Wed, 21 Aug 2002 11:20:58 +0200 From: Michael Gee Subject: MGNet's Conference Page There's a little bug on the mgnet's conference page The link to the 7th european multigrid conference should be to http://cox.iwr.uni-heidelberg.de/Conferences/emg02.html Yours, Michael Gee ------------------------------------------------------- Date: Thu, 22 Aug 2002 13:14:08 -0700 (PDT) From: laura nora Subject: Help in Finding Software I am wondering if you can help me find some free software on "using muligrid method in slid mechanics". It seems that there is no such code in the free software section. I am interested in using multigrid method to do structural static and dynamic analysis. I hope some day I can contribute something to this site. Thanks Laura ------------------------------------------------------- Date: Wed, 7 Aug 2002 14:45:01 -0400 (EDT) From: Ren-Cang Li Subject: Benchmarking elementary functions I am seeking applications or code pieces that heavily involve the evaluations of elementary functions (exp, log, trig., sqrt, x^y, etc.) to do a performance benchmark of available elementary math libraries (libm) from today's computer vendors. If you know or have any, please email me at rcli@cs.uky.edu. You help is greatly appreciated and will be acknowledged. Ren-Cang Li http://www.ms.uky.edu/~rcli Editor's note: Rencang works primarily for an HP Lab, on very long term ------------- leave from his university position, so check if you are uneasy about giving code to a computer vendor employee. ------------------------------------------------------- Date: Tue, 27 Aug 2002 14:22:09 +0100 (BST) From: John R Whiteman Subject: MAFELAP 2003, 21 - 24 June 2003 (First Announcement) THE MATHEMATICS OF FINITE ELEMENTS AND APPLICATIONS 2003 www.brunel.ac.uk/~icsrbicm/mafelap03 The ELEVENTH conference on the Mathematics of Finite Elements and Applications will be held at Brunel University during 21-24 JUNE, 2003 The internationally recognised MAFELAP conferences have been run by BICOM at Brunel University at three year intervals since 1972. In these conferences exposure is given to research on the theory and practical application of finite element methods. Invited speakers: M AINSWORTH, University of Strathclyde H T BANKS, North Carolina State University C CARSTENSEN, Technische Universitat, Vienna S N CHANDLER-WILDE, Brunel University L DEMKOWICZ, University of Texas at Austin J T ODEN, University of Texas at Austin C SCHWAB, Eidgenoessische Technische Hochschule, Zurich E SULI, University of Oxford M F WHEELER, University of Texas at Austin J R WHITEMAN, Brunel University The 2003 ZIENKIEWICZ LECTURE Lecture will be given by K MORGAN, University of Wales, Swansea The 2003 Isaac Newton Lecture will be given by F BREZZI, University of Pavia THE PROGRAMME AND CALL FOR PAPERS In addition to the invited lectures, the programme will contain LECTURES IN PARALLEL SESSIONS, SESSIONS OF POSTER PAPERS and MINI-SYMPOSIA. ANYONE WISHING TO ORGANISE A MINI-SYMPOSIUM IS REQUESTED TO CONTACT THE MAFELAP SECRETARY AS SOON AS POSSIBLE AT mafelap2003@brunel.ac.uk OR MAFELAP, BICOM, BRUNEL UNIVERSITY, UXBRIDGE, UB8 3PH, ENGLAND, OR TELEPHONE: 01895 203270 (UK) OR: -44-1895-203270 (INTERNATIONAL), OR FAX: 01895-203303. ANYONE WHO WISHES TO PRESENT EITHER A LECTURE IN A PARALLEL SESSION OF A POSTER PAPER IS ASKED TO SUBMIT AN ABSTRACT AS SOON AS POSSIBLE AND, IN ANY CASE, NOT LATER THAN 26 FEBRUARY 2003. THE CONFERENCE ORGANISERS WILL MAKE EVERY EFFORT TO ASSOCIATE TALKS WITH SUITABLE MINI-SYMPOSIA. URL: www.brunel.ac.uk/~icsrbicm/mafelap03 Contact: mafelap2003@brunel.ac.uk Another feature of MAFELAP 2003 will be the Isaac Newton Institute Mini-Symposium which will run throughout the conference and is a satellite event of the Newton Institute Programme Computational Challenges in Partial Differential Equations; 20 January - 4 July, 2003; for further details of the INI programme see http://www.newton.ac.uk/programs/CPD. ------------------------------ End of MGNet Digest **************************