From na-net@patience.stanford.edu Mon Oct 1 15:35:13 1990 Received: from sparky.EPM.ORNL.GOV by CS.UTK.EDU with SMTP (5.61++/2.5s-UTK) id AA14740; Mon, 1 Oct 90 00:10:18 -0400 Received: from msr.epm.ornl.gov by sparky.EPM.ORNL.GOV (4.1/1.34) id AA00685; Mon, 1 Oct 90 00:29:48 EDT Received: from beauty.Stanford.EDU by msr.epm.ornl.gov (5.61/1.34) id AA09146; Mon, 1 Oct 90 00:29:02 -0400 Received: from patience.Stanford.EDU by beauty.Stanford.EDU (4.0/inc-1.5) id AA05466; Sun, 30 Sep 90 21:20:03 PDT Received: by patience.Stanford.EDU (4.0/inc-1.5) id AA15248; Sun, 30 Sep 90 21:18:36 PDT Date: Sun, 30 Sep 90 21:18:36 PDT From: na-net@patience.stanford.edu Message-Id: <9010010418.AA15248@patience.Stanford.EDU> Return-Path: Subject: NA-NET distribution message Maint-Path: maintainer@na-net.stanford.edu To: na-net@patience.stanford.edu Reply-To: na-net@patience.stanford.edu Comment: requests, comments or problems to nanet@na-net.stanford.edu Comment: submissions to na@na-net.stanford.edu Status: RO NA Digest Sunday, September 30, 1990 Volume 90 : Issue 34 Today's Editor: Cleve Moler Today's Topics: Updated NA Net Mailing List Examples of "Pseudo-eigenvalues" Changes of Address for Youcef Saad Textbook Recommendation Sought New Book on Linear Control Design First Issue of SIAM Journal on Optimization Contents: SIAM J. Control and Optimization ICASE Meeting on Scalable Multiprocessors ICS'91 Call for Papers 5th Copper Mountain Conference on Multigrid Methods Multigrid Short Course Is There a "Public Domain MATLAB?" ------------------------------------------------------- From: The NA Net Date: Sun Sep 30 20:08:03 PDT 1990 Subject: Updated NA Net Mailing List Mark Kent has put a lot of effort into bringing the NA Net mailing list up to date. It now has 1558 entries. The list is used both for this NA Net News Digest and for the NA Net e-mail forwarding service. The later is accessed by sending mail to na.lastname@na-net.stanford.edu If there is an unambiguous match to 'lastname' in the mailing list, the mail will automatically be forwarded. If there is more than one match, you will be sent a message with the possible messages, together with the initials which must be prepended to distinguish among them. If there is no match, you will be sent a message saying so. Thanks, Mark, for updating the list. -- Cleve ------------------------------ From: Nick Trefethen Date: Fri, 21 Sep 90 22:31:47 +1000 Subject: Examples of "Pseudo-eigenvalues" Dear colleagues: I am in the process of writing a review of applications in numerical analysis of the theory of what I like to call "pseudo-eigenvalues" of non-normal matrices. If A is a matrix and eps is a positive real number, then a complex number z is defined to be an "eps-pseudo-eigenvalue of A " if it satisfies either of the following equivalent conditions: (i) z is an eigenvalue of A+E for some perturbation matrix E with norm(E) <= eps ; or (ii) The resolvent satisfies norm(inv(zI-A)) >= 1/eps . Many topics seem to be illuminated by this notion, such as the power-boundedness of families of matrices, the convergence of matrix iterations, the behavior of certain adaptive algorithms, and the stability of discretizations of p.d.e.'s. Can any of you help me by pointing out references in this area that I may have missed? For example, the definitions above were used by Varah in 1979; have other authors used them too, perhaps earlier? A plot of numerically computed pseudo-spectra (i.e., level curves of the norm of the resolvent) appears in a 1987 paper of Demmel; have any other such plots been published? More generally, I am always on the lookout for interesting examples of matrices whose eigenvalues are highly sensitive to perturbations, and have found matrices of this kind in the literature due to Kahan, Ruhe, and Higham, among others. Are there other good examples I may be unaware of? I would be grateful for any comments or references on these topics. Nick Trefethen School of Mathematics, University of New South Wales P.O. Box 1, Kensington, NSW 2033 Australia nick@hydra.maths.unsw.oz.au ------------------------------ From: Youcef Saad Date: Sat, 29 Sep 90 14:18:05 PDT Subject: Changes of Address for Youcef Saad Colleagues: From Oct. 1 to Oct 30, my address will be Youcef Saad, National Tsing Hua University Institute of Applied Math., Hsinchu, Taiwan 30043, Republic of China. Starting Nov. 1st 1990, my permanent address will be: Youcef Saad Computer Science Dept. University of Minnesota 4-192 EE/CSci Building 200 Union Street S.E. Minneapolis, MN 55455-0159 Phone: (612) 624-7804 (Office) (612) 625-4002 (CS dept) (612) 624-9802 (Office at the Minnesota Supercomp. Inst.) e-mail: saad@cs.umn.edu, na.saad@na-net.stanford.edu ------------------------------ From: Martin Berzins Date: Mon, 24 Sep 90 08:15:40 BST Subject: Textbook Recommendation Sought Introductory texts in mathematical software & scientific computation. Starting in January 1991, I have to teach a 20 lecture + practicals course to provide an introduction to numerical methods with a strong slant towards mathematical software and scientific computation. Does anyone know of a suitable text, preferably with examples in Pascal? The best I've managed to do so far are two out-of-print books - An Introduction to Numerical Computation in Pascal, Dew and James, Macmillan and -Numerical Methods A Software Approach, R.L. Johnston, Wiley. Both are out of print now. The book by Ortega and Poole on differential equations is very good and has some of the material but is too advanced for first-year students. Any suggestions? -- Martin Berzins (na.berzins) ------------------------------ From: Stephen Boyd Date: Mon, 24 Sep 90 08:58:35 MDT Subject: New Book on Linear Control Design New book available Linear Controller Design: Limits of Performance by Stephen Boyd and Craig Barratt (Stanford EE Dept.) is now available. The main topic of the book is closed-loop design and the computation of performance limits using convexity. The book introduces a standard framework for the control design problem and describes many practical design specifications in this framework. It is shown that many of these specifications are closed-loop convex; the corresponding control design problems can therefore be solved using the convex optimization algorithms described in the latter part of the book. Some special points of interest for NA people: * The whole point of the book is to apply more numerical computing to the problem of controller design than is commonly done. This is done by casting many controller design problems as infinite-dimensional nondifferentiable convex optimization problems. * Two standalone chapters cover norms of signals and systems, and their computation. * Two standalone chapters cover convex analysis and nondifferentiable convex optimization, emphasizing ellipsoid and cutting-plane methods. Many numerical examples illustrate the typical behavior of these algorithms. * Over 27000 lines of matlab source were written to generate the numerical examples and 216 plots and figures. To the authors' knowledge, the extent of the numerical computation in this book is unprecedented in a book on control systems. * Title: Linear Controller Design: Limits of Performance (428 pages, 216 figures, bibliography, index). * Publisher: Prentice-Hall Inc. * ISBN: 0-13-538687-X, Title Code: 538-686. -- Stephen Boyd & Craig Barratt ------------------------------ From: SIAM Publications Department Date: Wed, 26 Sep 90 11:01 EDT Subject: First Issue of SIAM Journal on Optimization SIAM JOURNAL ON OPTIMIZATION February 1991 Volume 1, Number 1 CONTENTS William C. Davidon Variable Metric Method for Minimization Roger Fletcher A New Variational Result for Quasi-Newton Formulae Kurt M. Anstreicher On the Performance of Karmarkar's Algorithm over a Sequence of Iterations Guangye Li Successive Element Correction Algorithms for Sparse Unconstrained Optimization V. Jeyakumar Composite Nonsmooth Programming with Gateaux Differentiability John R. Engels and Hector J. Martinez Local and Superlinear Convergence for Partially Known Quasi-Newton Methods Jong-Shi Pang, Shih-Ping Han, and Narayan Rangaraj Minimization of Locally Lipschitzian Functions Y. Dai, G. van der Laan, A. J. J. Talman, and Y. Yamamoto A Simplicial Algorithm for the Nonlinear Stationary Point Problem on an Unbounded Polyhedron Jiu Ding and Tien-Yien Li A Polynomial-Time Predictor-Corrector Algorithm for a Class of Linear Complementarity Problems C. T. Kelley and Ekkehard W. Sachs A New Proof of Superlinear Convergence for Broyden's Method in Hilbert Space Jorge J. More and Gerardo Toraldo On the Solution of Large Quadratic Programming Problems with Bound Constraints O. L. Mangasarian Convergence of Iterates of an Inexact Matrix Splitting Algorithm for the Symmetric Monotone Linear Complementarity Problem Virginia Torczon On the Convergence of the Multidirectional Search Algorithm EDITORIAL BOARD Kurt M. Austreicher Francisco O. Barahona Dimitri P. Bertsekas Frank H. Clarke Andrew R. Conn John E. Dennis Donald Goldfarb Clovis Gonzaga C. T. Kelley Masakazu Kojima O. L. Mangasarian Jose Mario Martinez Jorge J. More George Nemhauser Jorge Nocedal Michael L. Overton R. T. Rockafellar Roger W. H. Sargent Michael A. Saunders Robert B. Schnabel Alexander Schrijver Richard A. Tapia Eva Tardos PH. L. Toint Layne T. Watson Roger J.B. Wets Margaret H. Wright Yinyu Ye Stavros A. Zenios Francesco Zirilli Jochem Zowe For additional information, please contact SIAM 3600 University City Science Center Philadelphia, PA 19104-2688 telephone: 215-382-9800 fax: 215-386-7999 e-mail: siam@wharton.upenn.edu. ------------------------------ From: SIAM Publications Department Date: Fri, 28 Sep 90 14:30 EDT Subject: Contents: SIAM J. Control and Optimization Table of Contents SIAM J. Control and Optimization Vol. 29, No. 1, January 1991 J. S. Gibson and A. Adamian Approximation Theory for Linear-Quadratic-Gaussian Control of Flexible Structures B. Charlet, J. Levine, and R. Marino Sufficient Conditions for Dynamic State Feedback Linearization Manlio Gaudioso and Maria Flavia Monaco Quadratic Approximations in Convex Nondifferential Optimization D. S. Gilliam, B. A. Mair, and C. F. Martin An Inverse Convolution Method for Regular Parabolic Equations P. Acquistapace, F. Flandoli, and B. Terreni Initial Boundary Value Problems and Optimal Control for Nonautonomous Parabolic Systems Paul Tseng Applications of a Splitting Algorithm to Decomposition in Convex Programming and Variational Inequalities R. H. Kwong On the Linear Quadratic Gaussian Problem with Correlated Noise and its Relation to Minimum Variance Control U. Faigle and W. Kearn Note on the Convergence of Simulated Annealing Algorithms A. A. Stoorvogel The Singular H Control of Problem with Dynamic Measurement Feedback Henry Hermes Asymptotically Stabilizing Feedback Controls and the Nonlinear Regulator Problem Vilmos Komornik Rapid Boundary Stabilization of the Wave Equation G. da Prato, A. J. Pritchard, and J. Zabcyzk On Minimum Energy Problems Michael Pedersen Pseudodifferential Perturbations and Stabilization of Distributed Parameter Systems: Dirichlet Control Problems For additional information regarding the SIAM J. Control and Optimization, please contact Vickie Kearn, Publisher SIAM 3600 University City Science Center Philadelphia, PA 19104-2688 telephone: 215-382-9800 fax: 215-386-7999 e-mail: siampubs@wharton.upenn.edu ------------------------------ From: Joel Saltz Date: Mon, 24 Sep 90 00:48:51 EDT Subject: ICASE Meeting on Scalable Multiprocessors PRELIMINARY AGENDA UNSTRUCTURED SCIENTIFIC COMPUTATION ON SCALABLE MULTIPROCESSORS Ramada Inn, Kill Devil Hills, NC October 29-31, 1990 Sponsored by ICASE Monday, October 29, 1990 Manuel Salas, NASA Langley Research Center An Assessment of Unstructured-Grid Methods for the Analysis of Aircraft Fields Harold Trease, Los Alamos National Laboratory The Free-Lagrange Method on the Connection Machine Steven Hammond, Robert Schreiber, NASA Ames Research Center Mapping Unstructured Grid Problems to the Connection Machine Steven G. Kratzer, Supercomputing Research Center Unstructured Sparse QR Factorization on SIMD Computers Kapil K. Mathur, Thinking Machines Corporation Data Parallel Algorithms for the Finite Element Method Joel Saltz, ICASE, NASA Langley Research Center Runtime Compilation for Multiprocessors Ting-Fook Ngai, Stephen Lundstrom and Michael Flynn,Stanford University Run-Time Scheduling of Unstructured Scientific Computation on Scalable Multiprocessors Charles Koelbel, Rice University, Piyush Mehrotra, ICASE, Compiler Support for Unstructured Scientific Computations Steve Roy, Princeton University Parallelization of Adaptive Fast Multipole Algorithms Jack B. Dennis, Dataflow Computer Corporation Compiling Irregular Codes for Data Parallel Execution Tuesday, October 30, 1990 Roy Williams, California Institute of Technology Parallel Load Balancing for Parallel Unstructured Meshes Geoffrey Fox, Syracuse University Parallel Software and Algorithmic Issues for Fast Nbody Solvers John A. Board, Jr., James F. Leathrum, Jr., Duke University Mapping the Fast Multipole Algorithm onto MIMD Systems Shahid Bokhari, University of Engineering & Technology, Lahore On-line Parallel Binary Dissection Rainald Lohner, The George Washington University, Jose Camberos, Marshal Merriam, NASA Ames Research Center Parallel Unstructured Grid Generation David Keyes, Yale University and ICASE, Adaptive Refinement in Domain Decomposition Methods Calvin J. Ribbens, Virginia Polytechnic Institute and State University A Moving Mesh Scheme for Dynamically Adaptive Domain Decomposition R. Henderson, G. Karniadakis, Princeton University Hybrid Spectral Element-Finite Difference Techniques on Multiprocessing Environments Sukumar R. Chakravarthy, Sampath Palaniswamy Rockwell International Science Center Some Aspects of Single-Zone Structured-Grid CFD For Hypercube MIMD Computer Charbel Farhat, University of Colorado at Boulder L. Fezoui, S. Lanteri, INRIA, France Unstructured Compressible Flow Computations on the Connection Machine Wednesday, October 31, 1990 David Nicol, The College of William and Mary Algorithmic Issues in Mapping Workload Kirk R. Pruhs, Taieb F. Znati, Rami G. Melhem, University of Pittsburg Dynamic Mapping of Adaptive Finite Element Computations onto Linear Arrays Sharon L. Smith and Robert B. Schnabel, University of Colorado at Boulder Centralized and Distributed Dynamic Scheduling for Adaptive, Parallel Algorithms William Celmaster, BBN Advanced Computers Inc. Random-Access Bandwidth and Grid-Based Algorithms on Massively Parallel Computers Mo Mu, John Rice, Purdue University Performance of PDE Sparse Solvers on Hypercubes Edoardo S. Biagioni, Jan F. Prins, University of North Carolina Scan Directed Load Balancing for Highly-Parallel Mesh-Connected Computers Please contact Emily Todd by October 8 1990 if you are interested in attending. E-Mail emily@icase.edu US Mail Emily Todd MS 132C ICASE NASA Langley Research Center Hampton VA 23665 ------------------------------ From: Ruediger Esser Date: Mon, 24 Sep 90 08:52:29 MES Subject: ICS'91 Call for Papers CALL FOR PAPERS 1991 ACM International Conference on Supercomputing June 17-21, Cologne, Germany Conference Co-Chairmen Edward S. Davidson, University of Michigan, Ann Arbor, USA Friedel Hossfeld, Research Center Juelich (KFA), Germany Program Director Yoichi Muraoka, Waseda University, Tokyo, Japan Program Committee EUROPE AND AFRICA NORTH AND SOUTH AMERICA JAPAN AND FAR EAST U. Trottenberg (Chair) E. Houstis (Chair) T. Yuba (Chair) L.M. Delves D. Bailey T. Hoshino I. Duff F. Darema Y. Kanada W. Giloi D. DeGroot H. Kashiwagi J.R. Gurd G. Fox N. Koike G. Hoffmann E. Gallopoulos S. Nagashima W. Jalby D. Gannon H. Tanaka A. Lichnewski M. Heath Y. Tanakura P. Mueller-Stoy J. McGraw H. Terada T. Papatheodorou P. Messina K. Toda P. Sguazzero C. Polychronopoulos H. Wijshoff J. Rice H. Zima The fifth International Conference on Supercomputing is soliciting papers on significant new research results in the development and use of super- computer systems. Contributions should emphasize the novel aspects of the work being reported and should discuss their implications for future supercomputer development. Papers are welcome on topics including the following areas: ARCHITECTURAL DESIGN OF SUPERCOMPUTER SYSTEMS SOFTWARE SYSTEMS SUPPORT FOR SUPERCOMPUTING APPLICATIONS OF SUPERCOMPUTING SUPERCOMPUTING ALGORITHMS AND PERFORMANCE ANALYSIS Submissions Authors are invited to send five copies of the full manuscript in English to the program chairman of their region. Their addresses are: EUROPE AND AFRICA NORTH AND SOUTH AMERICA JAPAN AND FAR EAST Ulrich Trottenberg Elias Houstis Toshitugu Yuba GMD/F1 Dept. Computer Science ETL 1-1-4 Umesono Schloss Birlinghoven Purdue University Tukuba, Ibaraki D-5205 Sankt Augustin W. Lafayette, IN 47907 305 Japan Germany USA The deadline for submissions is DECEMBER 1, 1990. Authors will be notified of acceptance by February 20, 1991. Final, camera-ready versions of accepted submissions will be due by March 20, 1991. The Conference Proceedings will be published by ACM. SPONSORS: ACM-SIGARCH in association with AICA, BCS-PPG, CSRD, CTI, CWI, GI, GMD, INRIA, IPSJ, KFA, SBMAC, and SIAM-SIAGS. For further details, please contact: Ruediger Esser KFA-ZAM D-5170 Juelich, Germany Phone: +49-2461-61-6588 Fax: +49-2461-61-6656 E-mail: zdv003@djukfa11.bitnet ------------------------------ From: Steve McCormick Date: Fri, 28 Sep 90 07:54:40 -0600 Subject: 5th Copper Mountain Conference on Multigrid Methods *** Announcement and Call for Papers *** 5th COPPER MOUNTAIN CONFERENCE on MULTIGRID METHODS Copper Mountain, Colorado March 31-April 5, 1991 Organized by University of Colorado at Denver Front Range Scientific Computations, Inc. Society for Industrial and Applied Mathematics Sponsored by U.S. Air Force Office of Scientific Research National Science Foundation IBM Special Features Multigrid Circus Student Paper Competition Code/Algorithm Bake-Off Chairmen: Tom Manteuffel & Steve McCormick, University of Colorado at Denver Program Chairman: Jan Mandel, University of Colorado at Denver Program Committee: Joel Dendy, Los Alamos National Laboratory Craig Douglas, IBM Guy Lonsdale, Gesellschaft f. Math. u. Datenverarbeitung Seymour Parter, University of Wisconsin Joseph Pasciak, Brookhaven National Laboratory John Ruge, University of Colorado at Denver Klaus Stueben, Gesellschaft f. Math. u. Datenverarbeitung James Thomas, NASA Langley Pieter Wesseling, Delft University Workshop Chairman: Paul Frederickson, RIACS This conference traditionally provides a forum for interaction among basic researchers and practitioners. To promote this, morning and evening seminar sessions will be held and afternoons will be open for informal workshops, discussions, and special sessions. Anyone interested in organizing such a session should contact one of the chairmen. The conference will be held at the Copper Mountain Resort, about 75 miles west of Denver. Deluxe condominium accommodations and adjacent meeting rooms are in the Village Square Lodge at the base of the Copper Mountain F lift. PAPERS: Please send title, short abstract, mailing address, phone number, and e-mail address (if available) BY DECEMBER 1, 1990 to: Division of Extended Studies University of Colorado at Denver Campus Box 164 P.O.Box 173364 Denver, CO 80217-3364, USA Complete manuscripts for inclusion in the preliminary conference proceedings will be due MARCH 1, 1991. Selected papers will be refereed, with authors' consent, for publication in a special issue of the SIAM Journal on Numerical Analysis. REGISTRATION: The conference fee ($195 for SIAM members and $215 for non-members by March 1, $235 and $260 thereafter, $45 any time for students) should be paid with registration directly to the above address for the Division of Extended Studies. Please contact one of the conference chairmen for necessary forms. Conference fee includes preliminary proceedings, a reception, coffee breaks, and a banquet. MULTIGRID CIRCUS: Inspired by the finite element circus, we are including a circus for informal lectures and presentation of late- breaking research results. Anyone who attends the conference is welcome to lecture during these sessions, which are tenatively planned for late afternoon on the first four days. STUDENT PAPER COMPETITION: Travel assistance will be awarded to a few students who submit papers that we judge to be the best research papers. Deadline for submission of student papers is JANUARY 1, 1991. Please submit your paper with a brief statement of your background (institution, advisor, expected graduation date) to the Division of Extended Studies at the above address. Clearly mark it "Student Paper Competition." MULTIGRID CODE/ALGORITHM BAKE-OFF: Entrants must submit ONE test problem that has not already been submitted (Poisson's equation on a cube is already taken, sorry) with a code to generate the matrices, initial guesses, and right-hand sides in a known language (no copyright notices, please). This will be distributed to all involved. You will be responsible for timing your own program on some machine(s). You must also be willing to time other participants codes on your machine(s). You are not obligated to debug other people's codes, however. Scalar, superscalar, vector, parallel, and combination machines are welcome. Craig Douglas will oversee this mess, and will edit a joint paper with the participants. For more information, and the real rules, send e-mail to douglas-craig@cs.yale.edu or bells@yktvmv.bitnet. Deadline for entering is JANUARY 1, 1991. LODGING should be reserved directly with the Copper Mountain Resort by calling 1-800-458-8386 in the USA outside of Colorado, 1-800-332-3828 in Colorado, and 303-968-2882 overseas. (FAX: 303-968-2711.) The rates are $70 for a lodge room (one or two queen beds) and $142 for a two-bedroom condominium. Limousine and bus service is available from Stapleton International Airport in Denver. Detailed information is available on registration forms. SHORT COURSE: The conference will be preceeded by a week-long multigrid short course in Denver, March 25-29, 1991. For more information, please contact: Chaoqun Liu Computational Math Group, Campus Box 170 University of Colorado at Denver 1200 Larimer Street Denver, CO 80204 (303) 556-4807 e-mail: cliu@copper.colorado.edu FOR REGISTRATION FORMS/FURTHER INFORMATION: Tom Manteuffel or Steve McCormick Computational Math Group, Campus Box 170 University of Colorado at Denver 1200 Larimer Street Denver, CO 80204 (303)556-4807 e-mail: tmanteuf@copper.colorado.edu smccormi@copper.colorado.edu ------------------------------ From: Steve McCormick Date: Fri, 28 Sep 90 07:55:48 -0600 Subject: Multigrid Short Course *** MULTIGRID SHORT COURSE *** *** Information & Schedule *** University of Colorado at Denver March 25-29, 1991 Principal Lecturer: Achi Brandt Supporting Lecturers: John Adams, William Briggs, Chaoqun Liu, Steve McCormick, John Ruge Shortcourse Chairman: Chaoqun Liu Purpose: To provide an understanding of the principles and procedures for multilevel methods, especially for partial differential equations, including new multilevel approaches in computational fluid dynamics. Registration Fee: $500 (regular), $150 (student). Includes books and other course materials, refreshments, and computer lab access. Topics: . Basic tutorial . Advanced methods for PDE's (including multigrid procedures for general systems, nonlinearity, ellipticity/nonellipticity, time dependence, inverse problems, indefiniteness, discontinuities, singularities, performance prediction/analysis, constrained optimization) . Adaptive techniques (MLAT, FAC) . Algebraic methods (AMG) . Computational fluid dynamics (including finite volume element methods, high Reynolds number flow, steady and unsteady Navier-Stokes equations, Steady and unsteady Euler equations, flow transition, and two-phase porous flow) . Introduction to non-PDE multilevel techniques (including integral and integro-differential equations, fast dense matrix multiplication, many-body interactions, Direct solvers, large determinants, global discrete highly-nonlinear optimization, and multilevel Monte Carlo in statistical physics) Emphasis will be placed on concepts and basic principles, illustrated by concrete examples and results. Certain codes will be made available to participants for laboratory experimentation during and after the short course. Adjustments will be made to the schedule based upon the expressed interests of the participants. For Registration and Further Information, Please Contact: Chaoqun Liu Computational Mathematics Group University of Colorado at Denver 1200 Larimer Street, Campus Box 170 Telephone: (303) 556-4807 or (303) 556-4886 e-mail: cliu@copper.colorado.edu ------------------------------ From: Cleve Moler Date: Sun Sep 30 20:55:07 PDT 1990 Subject: Is There a "Public Domain MATLAB?" Is There a "Public Domain" MATLAB? >From time to time, I see references to, or get requests for, the "public domain" version of MATLAB. As the original author of MATLAB, and one of the founders of The MathWorks, I would like to explain how I regard "public domain" MATLAB. There are two versions of MATLAB. I wrote the first, which we now refer to as "classic" MATLAB, over the period from 1977 to 1984, while I was on the faculty at the University of New Mexico. It is an interactive matrix laboratory, written in Fortran, which uses some of the subroutines from LINPACK and EISPACK. I distributed a few hundred copies of the source code, usually charging a small service charge, and including a letter requesting that the code not be redistributed. I never used the term "public domain". The second version, written in C by Steve Bangert and John Little, is the basis for a family of products from The MathWorks, Inc., a company which Bangert, Little and I founded in 1985. These products are called PC-MATLAB, Mac-MATLAB, Pro-MATLAB, etc. I obviously recommend that anyone interested in using MATLAB acquire the MathWorks version appropriate for his or her machine. In addition to my commercial interest, I believe the MathWorks versions are preferable scientifically, educationally, and, in the long run, economically. The MathWorks versions: * Are faster in execution, * Have much better storage management, * Include powerful graphics, * Are extensible and programmable, * Can be expanded with sophisticated "toolboxes", * Are supported by scientific software professionals. The only feature of classic MATLAB that is not present in modern MATLAB is the "chop" function which allows the simulation of shorter precision arithmetic. It is an interesting curiosity, but it is no substitute for roundoff error analysis and it makes execution very slow, even when it isn't used. I know of several serious bugs in classic MATLAB, particularly in logical and looping operations, but I don't intend to fix them. In fact, there have been no fixes made to the code since about 1982. I stopped distributing any copies myself 4 or 5 years ago. The number of computers for which MathWorks MATLAB is not available is declining as old machines are retired and new machine versions are announced. A few other commercial systems, for example SCT's CTRL-C, are based on classic MATLAB. That's OK. CTRL-C, was done with my permission and it helped establish MATLAB in control and systems engineering. Now the company is a worthy competitor. I realize that classic MATLAB is available on a few bulletin boards and through some "freeware" services. In some cases, unauthorized statements about public domain software are included. I have regarded this as a mixed blessing. It certainly gives the MATLAB approach to computing valuable exposure, but I am afraid that some users of classic MATLAB do not realize how inferior it is to the MathWorks products. In summary, here is my position: * There is no such thing as "public domain" MATLAB. * I no longer distribute "classic" MATLAB. * The code and documentation of classic MATLAB cannot be used for commercial purposes without my permission. * I would appreciate it if anybody making a copy of classic MATLAB for personal or educational use would include this statement with it. -- Cleve Moler moler@mathworks.com, or, na.moler@na-net.stanford.edu ------------------------------ End of NA Digest ************************** -------