From nacomb@surfer.EPM.ORNL.GOV Sun May 10 14:08:18 1992 Return-Path: Received: from surfer.EPM.ORNL.GOV by CS.UTK.EDU with SMTP (5.61++/2.8s-UTK) id AA24281; Sun, 10 May 92 14:08:12 -0400 Received: by surfer.EPM.ORNL.GOV (5.61/1.34) id AA11204; Sun, 10 May 92 14:07:59 -0400 Date: Sun, 10 May 92 14:07:59 -0400 From: nacomb@surfer.EPM.ORNL.GOV (NA-NET) Message-Id: <9205101807.AA11204@surfer.EPM.ORNL.GOV> To: na.digest-list@surfer.EPM.ORNL.GOV Subject: NA Digest, V. 92, # 19 Status: RO NA Digest Sunday, May 10, 1992 Volume 92 : Issue 19 Today's Editor: Cleve Moler The MathWorks, Inc. moler@mathworks.com Today's Topics: Farouk Odeh Congratulations to Alan George Photos from Golub Festivities Address Change for Andrew Stuart Info on PC-style Math Coprocessors Laplace's Equation with Nontrivial Boundary Condtions Bibtex File on Least Squares Date of Conference in Bangalore, India Any Large Linear Algebra Problems? U. S. Legislation on Foreign Research Assistants Conference: Scientific Computation on Workstations Brazilian School on High Performance Scientific Computing Parallel Course at CERFACS Contents: Linear Algebra and its Applications Submissions for NA Digest: Mail to na.digest@na-net.ornl.gov. Information about NA-NET: Mail to na.help@na-net.ornl.gov. ------------------------------------------------------- From: Bill Henshaw Date: Fri, 8 May 92 15:11:07 EDT Subject: Farouk Odeh It is with great sadness that we must tell you that Farouk Odeh passed away this week. Farouk, who had been at IBM Research for over thirty years, was the manager of the differential equations group. He will be greatly missed by all his friends and colleagues. We knew him not only as an outstanding and insightful mathematician, but also as a gracious, friendly, and intuitive man with a gentle sense of humor who seemed to know more than most of us about the poetry of life. ------------------------------ From: Gene Golub Date: Sun, 3 May 92 20:03:14 CDT Subject: Congratulations to Alan George Congratulations to Alan George on his election to the Royal Society of Canada. Alan's work on sparse matrices has been of great importance to many areas of application. Gene Golub ------------------------------ From: Eric Grosse Date: Mon, 4 May 92 10:32 EDT Subject: Photos from Golub Festivities A few of Tony Chan's photos from Gene Golub's 15th birthday celebration in Minnesota are available by anonymous ftp from research.att.com in the directory netlib/photo/golub92. These are (binary) GIF-format image files. If "ftp" and "GIF" sound foreign to you, now is probably not the time to explore the mysteries of image file formats. On the other hand, if you're a graphics enthusiast, download and enjoy! More generally, it would be possible and perhaps useful to compile group photos from conferences and photos of individual mathematicians, both current and historical. Aside from the cost in disk space and network bandwidth, the only disadvantage that occurs to me is the risk of abuse by digital image manipulation. I welcome advice from anyone with insight. Best wishes, Eric ------------------------------ From: Andrew Stuart Date: Mon, 4 May 92 08:01:51 -0700 Subject: Address Change for Andrew Stuart As of April 1st 1992, my new address is: Andrew Stuart Program in Scientific Computing and Computational Mathematics Durand-252 Stanford University California 94305-4040, USA. Phone: 415-723-8142 Fax: 415-723-1778 e-mail: stuart@sccm.stanford.edu ------------------------------ From: Edward A. Celarier Date: Sun, 3 May 1992 21:02 EST Subject: Info on PC-style Math Coprocessors I am considering the purchase of a coprocessor for my 80386-based p.c. There seem to be a number of contenders in the 8087-plug-compatible league: IIT, Cyrix, Intel, and Weitek, in addition to some other versions. (My PC has a socket for a special processor from Weitek, for example.) Can someone point me in the direction of some reliable information about the numerical aspects of these? Are they all IEEE-compliant? Are 80387-plug-compatible chips really all equivalent, state-for-state, to the Intel chip? I would appreciate e-mail to CELARIER@CEBAF2.CEBAF.GOV. Many thanks, Edward A. Celarier Dept of Chemistry Hampton University Hampton, VA [Editor's Note: Other people might be interested in this answer to these questions, too. Please submit any definitive response to na.digest@na-net.ornl.gov. Thanks. -- Cleve] ------------------------------ From: David Billinghurst Date: Wed, 6 May 92 14:28:47 -1000 Subject: Laplace's Equation with Nontrivial Boundary Condtions We are starting a study on anode consumption in an electro-reduction process. This is a moving boundary problem. The current flow is determined by Laplace's equation in multiple domains, and the anode surface ( one of the internal boundaries ) is consumed at a rate proportional to the local current density. Physically the process is self-regulating, since regions of the anode that are closer to the cathode draw a higher current and burn back preferentially. In addition there are two very different time scales present: the current relaxes (almost) instantaneously, while the anode is consumed slowly. We plan to solve for the current flow at each time step, and adjust the boundary explicitly. This reduces the problem to one of solving Laplace's equation in multiple irregular regions, with conductivity differences of two or three orders of magnitude, a couple of hundred times with small changes to the boundary location each time. We would appreciate hearing from anybody who 1. Can point us to any relevent literature. 2. Has worked on similar problems analytically or numerically. Bob Hannaford David Billinghurst hannar@comres.cra.com.au billingd@comres.cra.com.au Comalco Research Centre 15 Edgars Rd Thomastown Vic 3074 Phone: +61 3 469 0777 Australia Fax: +61 3 462 2700 ------------------------------ From: Ake Bjorck Date: Thu, 7 May 92 15:39:10 +0200 Subject: Bibtex File on Least Squares I have compiled a bibtex reference base covering aspects of numerical solution of least squares problems. It contains about 520 references, and in particular the references for my chapter on Least Squares Methods in "Handbook of Numerical Analysis, Volume I, North Holland 1990". I am now making it available by anonomous ftp at math.liu.se in the directory pub/references The bibtex base has been modelled after a bibtex reference base created by Pete Stewart (see NA Digest Vol. 91, No. 9). I am using almost all of his conventions, with respect to citation keys, keywords, etc. I have also found Pete's program to search a bib file very useful for browsing or for creating sub-bibliographies. This program is contained in the file bibsearch.tar and available by anonymous ftp at thales.cs.umd.edu in the directory pub/references Ake Bjorck akbjo@math.liu.se ------------------------------ From: K.S.Yajnik Date: Tue, 5 May 92 19:37:06 EDT Subject: Date of Conference in Bangalore, India Hello, Our announcement in last week's Digest of the IMACS Int Symposium on Math. Modelling and Scientific Computing inadvertently omitted the date of the conference. I apologise for the incomplete announcement. The date and place are: December 7-11, 1992 Bangalore, India If you have any questions please write/e-mail/fax to: 1) K.S.Yajnik, Head, C-MMACS, National Aeronautical Laboratory Belur Campus, Bangalore Tel #: (91)(812)574649 e-mail: yajnik@cmmacs.ernet.in fax: (91)(812)560392 2) S.K.Dey, Dept of Math., Eastern Illinois Univ. Charleston, IL 61920-3099 Tel # : (217)581-3217 Fax #: (217)581-5188 e-mail: cfskd@ux1.cts.eiu.edu 3) E.J.Kansa, Lawrence Livermore National Lab P.O. Box 808, L-200 Livermore CA 94551-0808 e-mail: kansa@s118.es.llnl.gov ------------------------------ From: Alan Edelman Date: Fri, 8 May 92 18:14:09 PDT Subject: Any Large Linear Algebra Problems? SAY IT ISN'T SO!! Last month, I initiated my second large dense linear algebra survey. So far, I have received only ONE definitive response. Is large dense linear algebra an unimportant subject? Do supercomputers currently need large dense linear algebra libraries or are more specialized toolboxes needed for now? Perhaps my survey comes at a busy time of the year or perhaps I am targeting the wrong audience. Right now, I have no choice to conclude based on the data that I have so far received that nobody is working on solving a dense eigenvalue problem of size bigger than 5000 and almost nobody is solving large dense linear systems not arising from a boundary element calculation. Is this true? If you are even VAGUELY aware of large dense eigenvalue problems or large dense linear systems other than boundary element calculations, I beg you to respond with either a completed form or by forwarding this form to your colleague. Thank you -- Alan Edelman THE SECOND ANNUAL LARGE DENSE LINEAR ALGEBRA SURVEY Alan Edelman, Dept of Mathematics, University of California, Berkeley, CA 94720 My calendar file tells me that it is now time for the second annual large dense linear algebra survey. This year, I hope to cover two subjects: 1. large dense linear systems (like last year) 2. large dense eigenvalue problems It is not within my resources to print out and mail letters to every science department at universities and industries, so I beg readers to spread my survey by word of mouth, and strongly urge you and your colleagues to participate. Readers interested in last year's survey are invited to obtain it by anonymous FTP from math.berkeley.edu in /pub/edelman/survey1991. In order to confine the topic of discussion, we do not consider any matrix that can be parameterized by significantly fewer than n^2 elements to be dense. Thus a Toeplitz matrix or a matrix of the form A*A' where A is sparse are not considered dense in this context. I will allow matrices generated for Panel Methods and Moment Methods to be considered dense. Part 1: Linear Systems A. Largest LU or QR factorization Has anyone solved a system of size bigger than 60,000 using traditional LINPACK or LAPACK style methods? If so, please tell me the time it took, why you solved the problem, how accurate the solution was, and how you know. Have you tried a condition estimator for your problem? Did you consider a Krylov space based iterative method for your problem? B. I an interested in the solutions to any dense matrix bigger than 20,000 for purposes other than Panel Methods and Moment Methods. Part II: Eigenvalue Problems A. I am interested in all eigenvalues problems for dense square matrices of order at least 5,000. Please carefully describe where you are in the range of wanting all eigenvalues and all eigenvectors to merely wanting one eigenvalue. Do your eigenvalues fall along a curve or cluster or are they scattered and well separated? Have you evaluated the conditioning of your problem, and if so, how? B. Would you like to solve a large dense eigenvalue problem of order greater than 50,000 if you had the resources? How large can you foresee your problem getting at this point? Name: Affiliation: Address: How big is your matrix? What kind of matrix? (Symmetric, complex, double precision?) What is the solution method? What is the time for solution? On which machine? How accurate was your solution? (Explain how you know) What is your confidence in this accuracy? Could the newly released LAPACK be used for your problem? (LAPACK replaces LINPACK and EISPACK as the current best linear algebra software library. Information is available through netlib.) Please describe your application area. References: 1. If appropriate please refer to the publication most closely related to your particular problem. In most cases this will be an article authored by you or a member of your group. 2. Please suggest an expository article or book that would be most accessible to a non-specialist trying to understand your problem. ------------------------------ From: Horst D. Simon Date: Fri, 8 May 92 14:46:47 -0700 Subject: U. S. Legislation on Foreign Research Assistants Dear na-net readers, I would like to bring your attention a bill which is currently going through hearings in the house science subcommittee. I have received the following information from a colleague here at NASA Ames. I believe that the goal of this bill, an attempt of restricting the ability of foreign graduate students to work as research assistants, will severely impact the research in many graduate departments in a negative way, while not addressing at all the problem of increasing enrollment by U.S. students in math and science graduate departments. This should be of concern to many na-net readers. -- Horst Simon. TO: NAFSAnet Users FROM: Lisa Jacobson Treacy, Amy Yenkin, NAFSA Central Office RE: New Legislation on Foreign R.A.s; Forms Available from GPO (NAFSA Update No. 178) DATE: May 7, 1992 1. Bill Introduced on Research Assistantships for Foreign Students In an attempt to encourage colleges and universities to recruit more Americans in doctoral programs, especially in the fields of math and science, Rep. Paul Henry (R-MI) recently introduced the "American Math and Science Student Support Act" (HR 4595). The bill would impose strict reporting requirements as part of grant applications for federal funds which include: 1. the name and country of origin of each nonimmigrant employed as a research assistant on a federal grant, 2. each such alien's intent toward seeking permanent residence status, 3. a description of efforts made to hire U.S. citizens or permanent residents, and 4. why no U.S. citizens or permanent residents were available. On April 29th, the House Science Subcommittee held a hearing at the bill. NAFSA was present at the hearing and submitted testimony for the record. Although all the witnesses agreed that the low number of Americans pursuing PhDs is a problem, all but one were critical of the remedy offered by the bill. ON THE BASIS OF THE TESTIMONY, IT SEEMS UNLIKELY THAT HR 4595 WILL MOVE FORWARD. However, based on a May 6 article in the Chronicle of Higher Education, the underlying issue of the role of foreign students at U.S. institutions is likely to continue to come under increased scrutiny. A detailed story on the bill and NAFSA's testimony will be featured in the next issue of the Government Affairs Bulletin. Subscribers will receive the May issue in the next two weeks. ------------------------------ From: Wayne Enright Date: Thu, 7 May 1992 16:05:38 -0400 Subject: Conference: Scientific Computation on Workstations Scientific Computation on Workstations: Current and Future Environments Preliminary Announcement: A symposium on ``Scientific Computation on Workstations: Current and Future Environments'' will be held in Toronto on September 17, 1992, to be followed by open sessions of the IFIP Working Group 2.5 (Numerical Software) on September 18 and the morning of September 19. Recent hardware and software developments have led to powerful low-cost workstations which are fast enough and have sufficient memory and disk space to permit the effective solution of many significant problems that arise in scientific and engineering applications. Problem solving environments that exploit the advantages such workstations offer are being developed to allow practitioners to solve their problems without requiring them to be systems or programming experts. In the symposium an overview will be presented of some of these environments and of how they are likely to evolve in the next few years. Feature presentations by Cleve Moler (MATLAB - Mathworks), Keith Geddes (MAPLE - Waterloo), Wayne Enright (ODEs - Toronto), Eugene Fiume (Graphics - Toronto) as well as representatives from NAG and IMSL have been planned. The open sessions of the Working Group will feature presentations, mostly by members of the Group, of current work on Numerical Software -- including such topics as programming language facilities, benchmarks and performance, mathematical methods, and education issues. There is a possibility that some time will be available for short presentations by others on September 18th. Anyone interested in contributing such a presentation should contact one of the organizers by the end of May. The meetings on September 17 and 18 will be held at the Delta Chelsea Inn. Room rates will be $76 single and $91 double. Hotel reservations should be made directly with the hotel: Delta Chelsea Inn, 33 Gerrard Street West, Toronto, M5G 1Z4, Canada Phone: (416) 595-1975, Fax: (416) 585-4362, Group Code (or 'Q-name'): GFRORE. Reservations should be made as soon as possible as only a limited number of rooms are available at this special rate. The registration fee for the symposium is $25 and advance registration is needed to ensure that space is available. To register, or to be placed on our mailing list to receive more information in the future, please contact one of the organizers, W.H. Enright or T.E. Hull, at: Department of Computer Science University of Toronto Toronto M5S 1A4 Canada email: enright@na.utoronto.ca tehull@na.utoronto.ca The symposium will be supported jointly by WG 2.5, the Information Technology Research Centre of Ontario, and the Natural Sciences and Engineering Research Council of Canada. ------------------------------ From: Carlos de Moura Date: Sat, 9 May 92 15:51:17 +0200 Subject: Brazilian School on High Performance Scientific Computing BRAZILIAN SCHOOL ON HIGH PERFORMANCE SCIENTIFIC COMPUTING Rio de Janeiro, August 3-7, 1992 Support and Organization: IBM-Brasil and LNCC/CNPq, Rio Confirmed lecturers Enrico Clementi Universite de Strasbourg I - Louis Pasteur CRS4 - Centro Ricerca e Sviluppo, Studi Superiori in Sardegna 1. Evolution of Computers and of Computer Use in Science 2. The MOTECC Initiative Craig Douglas Yale University & IBM Yorktown Heights Theory and Implementation of Multigrid Methods: Why It Might Work and How to Make It Run Like a Bat Out of Hell on Serial and Parallel Computers Peter M. Kogge IBM Senior Technical Staff (FSC), IEEE Fellow Declarative Computing Marianela Lentini Universidad Simon Bolivar An implementation on transputers of the Simplex Method Gerard Meurant CEA - Centre d'\'Etudes de Limeil-Valenton Computational Linear Algebra Ulrich Trottenberg GMD-Bonn & Universit\"at K\"oln 1. Parallel architetures and programming models 2. Parallel strategies for matrix, grid and multi-grid data structures Olof Widlund Courant Institute of Mathematical Sciences, New York University Domain decomposition algorithms for elliptic partial differential equations Paul Woodward University of Minnesotta Organizing Committee M. Annarumma - IBM Brasil A. Cascon - LNCC & UFF A. Gadelha Vieira - LNCC & UFRJ A. Santoro - CBPF & FermiLab Visiting Scholar J. P. Schiffini - IBM Brasil R. Shellard - PUC/RJ & CERN Visiting Scholar Chairman: C. A. de Moura - LNCC & College de France Visiting Scholar ------------------------------ From: Iain Duff Date: Fri, 08 May 92 21:39:52 BST Subject: Parallel Course at CERFACS CERFACS (European Centre for Research and Advanced Training in Scientific Computation) Will Organize An Introduction to Parallel Computing A three-day advanced short course Tuesday 9th June - Thursday 11th June 1992 in Toulouse, France AIM OF COURSE This course on parallel computing will be held at CERFACS, Toulouse from June 9th to 11th, 1992 under the auspices of CERFACS. The course is aimed at scientists in industry and academia who wish to learn about parallel computing and familiarize themselves through hands-on experience with a range of parallel computers. These will include -ALLIANT FX/80 and FX/2800 -CONVEX C220 -IBM 950 -CRAY-2 -CM2 from Sophia -IPSC2 from IRISA -BBN TC2000 Throughout the course, there will be a strong emphasis on hands-on experience and it is the intention that students will finish the course with a basic knowledge of parallelism and how to appreciate, compare, and use a range of different parallel architectures. PROGRAMME Tuesday, 9th June 1992 Introduction to vectorization, J. DONGARRA Introduction to parallel architectures, J. DONGARRA Shared Memory computers, P. AMESTOY Distributed Memory computers, R.TUMINARO Description of machines and access, I. D. LEVINE Wednesday, 10th June 1992 Programming parallel machines, I. D. LEVINE, S. SMITH, R. TUMINARO BLAS and LAPACK M.DAYDE Solution of sparse equations, I. DUFF, P.AMESTOY Thursday, 11th June 1992 Tools and Parallel Programming, W. JALBY Block iterative methods D. RUIZ Multigrid Techniques, R. TUMINARO Hands-on....... applications Gala dinner (optional) ENROLLMENT Participants are advised to register before May 25 by Email, fax or phone to Dominique BENNETT, CERFACS, 42 Ave Gustave Coriolis, 31057 TOULOUSE Cedex, FRANCE, Tel : (33) 61 19 31 31 Fax : (33) 61 19 30 30 EMail : bennett@cerfacs.fr The enrolment fee is 5,930. FF (of which 930F is VAT) which includes lunch and all refreshments. For full-time students the fee is reduced to 3,558 FF (of which 558 F is VAT). A written request for this reduction, together with verification of student status, must be submitted along with your application. Delayed registrations will increase the registration fees by 10%. The CERFACS' "agrement" number is 7331P003131. PAYMENT FOR REGISTRATION FEES * cheque made out to GIP CERFACS * or by bank transfer to Barclays Bank, 3 rue Genty Magre, 31000 Toulouse, Bank Code 30588, Agency Code 12501, Account 03092257101, RIB key 02 * or in cash on the first day of the course ------------------------------ From: Richard Brualdi Date: Mon, 4 May 92 17:49:45 CDT Subject: Contents: Linear Algebra and its Applications LINEAR ALGEBRA AND ITS APPLICATIONS Contents Volume 171, July 1, 1992 Fuad Kittaneh (Bloomington, Indiana) A Note on the Arithmetic-Geometric-Mean Inequality for Matrices 1 Charles A. Hall and Xiu Ye (Pittsburgh, Pennsylvania) Construction of Null Bases for the Divergence Operator Associated With Incompressible Navier-Stokes Equations 9 Svatopluk Poljak (Praha, Czechoslovakia) Minimum Spectral Radius of a Weighted Graph 53 Curtis Greene (Haverford, Pennsylvania) Proof of a Conjecture on Immanants of the Jacobi-Trudi Matrix 65 Jianming Miao and Adi Ben-Israel (New Brunswick, New Jersey) On Principal Angles Between Subspaces in Rn* 81 Arthur M. DuPre (Newark, New Jersey) and Seymour Kass (Boston, Massachusetts) Distance and Parallelism Between Flats in Rn 99 Ling Chen (Guangzhou, China) and Chi Song Wong (Windsor, Ontario, Canada) Inequalities for Singular Values and Traces 109 Jiang Erxiong (Shanghai, China) A Note on the Double-Shift QL Algorithm 121 J. Pasupathy and R. A. Damodar (Bangalore, India) The Gaussian Toeplitz Matrix 133 B. Uhrin (Budapest, Hungary) Touching Points of a Star-Shaped Set With an Affine Subspace 149 Daniel Hershkowitz (Haifa, Israel) Recent Directions in Matrix Stability 161 Yang Shangjun (Hefei, Anhui, People's Republic of China) A Note on the Exponent Set of Primitive Minimally Strong Digraphs 187 P. Turkowski (Krakow, Poland) Structure of Real Lie Algebras 197 Sung Je Cho, Seung-Hyeok Kye, and Sa Ge Lee (Seoul, Korea) Generalized Choi Maps in Three-Dimensional Matrix Algebra 213 Wilbur N. Dale and Malcolm C. Smith (Columbus, Ohio) A Note on Eventually Time-Invariant Systems 225 Chin Chang and Tryphon T. Georgiou (Minneapolis, Minnesota) On a Schur-Algorithm Based Approach to Spectral Factorization: Connection With the Riccati Equation 233 James V. Burke (Seattle, Washington) and Michael L. Overton (New York, New York) Stable Perturbations of Nonsymmetric Matrices 249 Book Review Stephen G. Nash (Fairfax, Virginia) Review of Fundamentals of Matrix Computations by David S. Watkins 275 Author Index 279 ------------------------------ End of NA Digest ************************** -------