From na-net@na-net.stanford.edu Sun Mar 13 13:53:41 1988 Received: from anl-mcs.ARPA by antares.mcs.anl (3.2/SMI-3.2) id AA17939; Sun, 13 Mar 88 13:53:37 CST Received: from Patience.stanford.edu (9a000824) by anl-mcs.ARPA (4.12/4.9) id AA23076; Sun, 13 Mar 88 13:50:43 cst Received: by Patience.stanford.edu (4.0/inc-1.3) id AA11375; Sun, 13 Mar 88 11:48:18 PST Date: Sun, 13 Mar 88 11:48:18 PST From: na-net@na-net.stanford.edu Message-Id: <8803131948.AA11375@Patience.stanford.edu> Return-Path: Subject: NA-NET distribution message Errors-To: postmaster@na-net.stanford.edu Maint-Path: maintainer@na-net.stanford.edu To: na-net@na-net.stanford.edu Reply-To: na-net@na-net.stanford.edu Comment: requests, comments or problems to nanet@na-net.stanford.edu Comment: submissions to na@na-net.stanford.edu Comment: alternate address: na%na-net@score.stanford.edu Status: R NA Digest Sunday, March 13, 1988 Volume 88 : Issue 11 Today's Editor: Cleve Moler Today's Topics: Visiting Positions at NTH, Norway Hankel and Toeplitz Matrices NATO summer workshops New Book on Boundary Value Problems for ODEs Solution of Quartic Equations ------------------------------------------------------- From: Hans Munthe-Kaas Date: 7 Mar 88 15:36 +0100 Subject: Visiting Positions at NTH, Norway VISITING POSITIONS AT THE SUPERCOMPUTING CENTRE OF THE NTH IN NORWAY At The Norwegian Institute of Technology (NTH) and the research institute SINTEF a Cray X-MP/28 was installed in January -87. At the same time a group called Section for Industrial Mathematics (SIMa) was founded. This group is a link between the mathematical sciences department at the NTH and the users of the supercomputer. NTH and SINTEF are situated in Trondheim which is the centre for technological R&D in Norway. Combined they have more than 3500 people employed in research, and about 6000 students at NTH. The SIMa group is conducting research in both algorithm development and in applications of supercomputing. Our main areas of interest are currently: Algorithms: Image processing, Numerical ODE, Linear Algebra, Inverse Problems. Applications: Marine Hydrodynamics, Oil reservoir simulations, Image processing of NMR / tomographic pictures, Civil engineering, Electrical engineering, Mechanical engineering, Chemical engineering, Computer animation. THIS NOTE IS TO GET IN CONTACT WITH RESEARCHERS INTERESTED IN SUPERCOMPUTING, BOTH FROM AN APPLICATIONS AND FROM AN ALGORITMIC POINT OF VIEW. We can offer (depending on the length of stay): Travel expences, Local expences, Office space, Cpu-time on CRAY, Salary up to 3 months. Besides this, Trondheim is a nice town in the middle of Norway with its roots back in the viking ages. A visit to Trondheim can well be combined with holiday in Norway. Interested people should contact: Prof. B. Pettersen, arpa: b-pettersen%vax.runit.unit.uninett@nta-vax bitnet: BJORNAR at NORUNIT or Prof. S.P. Norsett, nanet: na.norsett@score.stanford.edu arpa: norsett%vax.runit.unit.uninett@nta-vax bitnet: NORSETT at NORUNIT Mail: SIMa/RUNIT N-7034 Trondheim Norway ------------------------------ From: Per Hansen Date: Tue, 8 Mar 88 15:21:05 EST Subject: Hankel and Toeplitz Matrices Matrix-vector-multiplication with Hankel and Toeplitz matrices. Does anyone have algorithms or, preferably, Fortran programs for fast multi- plication of a vector by a matrix with Toeplitz- or Hankel-form? Please reply via e-mail to: na.hansen@na-net.stanford.edu. Per Christian Hansen Copenhagen University Observatory Oster Voldgade 3, DK-1350 Copenhagen K, Denmark ------------------------------ From: Gene Golub Date: 8 Mar 88 23:16 +0100 Subject: NATO summer workshops As indicated in a previous message, there will be a NATO Advanced Study Institute (ASI) on NUMERICAL LINEAR ALGEBRA, DIGITAL SIGNAL PROCESSING and PARALLEL ALGORITHMS in Leuven, Belgium during the period August 1-12. Applications must be sent to Danny Sorensen (na.sorensen@na-net.stanford.edu) or Paul Van Dooren (na.vandooren@na-net.stanford.edu) by March 20, 1988. More detailed information and an application form have been previously distributed via NA-NET, and a copy of the announcement can be obtained via netlib. There will also be MINI-WORKSHOPS in association with the ASI during the period of July 18 thru Aug 26. All are invited to submit proposals, even if they do not plan to attend the ASI .The MINI-WORKSHOPS of, say, 2 days each should be organized around certain themes. We can guarantee some support (housing/meals). The meetings scheduled so far are : Adaptive filtering (Bellanger) Aug. 16-17 Identification (De Moor-Vandewalle) Aug. 18-19 VLSI architectures for real time sign. proc. (Cattoor-Deman) July 25-29 Send proposals to Van Dooren or Sorensen. Hope to see you in Leuven, Gene Golub ------------------------------ From: Bob Russell Date: 8 Mar 88 21:54 -0800 Subject: New Book on Boundary Value Problems for ODEs Uri Ascher, Bob Mattheij, and I (Bob Russell) have recently completed our book Numerical Solution of Boundary Value Problems for ODEs (ISBN 0-13-627266-5). We have attempted to make it a comprehensive treatment of the topic, suitable for both researchers and graduate students. The publisher is Prentice Hall - their series for Computa- tional Mathematics (in which some are unfortunately out of print). Chapter titles: 1. Introduction 2. Review of Numerical Analysis/Math. Background 3. Theory of ODEs 4. Initial Value Methods 5. Finite Difference Methods 6. Decoupling 7. Solving Linear Equations 8. Solving Nonlinear Equations 9. Mesh Selection 10. Singular Perturbations 11. Special Topics Appendices with Codes Ordering Information: US: 201-767-5937 Prentice-Hall, College Operations, Englewood Cliffs, NJ 07632 Canada: Carl Henderson, Prentice-Hall Canada,1870 Birchmount Road, Scarborough, Ontario M1P 2J7 International: Simon & Schuster International Customer Service Group, 200 Old Tappan Road, Old Tappan, NJ 07675, USA ------------------------------ From: Douglass Turner Date: 11 Mar 88 15:05:11 GMT Subject: Solution of Quartic Equations Hello, does anyone know of a good, robust, method to find all roots of a quartic equation?. I am a computer graphics person and am writing code to intersect a ray with a quartic (as part of a ray tracing program). The problem boils done to finding valid roots of a quartic. I have heard that direct solution is prone to numerical instability, so an iterative technique is called for. I do have a way of getting good inital guesses to start a rather slow iterative method like regula falsi, but I'm looking for something that converges as quickly as possible. Perhaps a hybrid method of some kind. Any code, pseudo-code, or description of algorithm would be much appreciated. I intend to post a synopsis to the comp.graphics group (and this one if someone wishes). Thanks. Douglass Turner ------------------------------ End of NA Digest ************************** -------