From research.att.com!surfer.EPM.ORNL.GOV!nacomb Sun Jun 23 20:02:05 0400 1991 Received: by pyxis; Sun Jun 23 20:02 EDT 1991 To: pyxis!ehg Received: by inet.att.com; Sun Jun 23 20:02 EDT 1991 Received: by surfer.EPM.ORNL.GOV (5.61/1.34) id AA07167; Sun, 23 Jun 91 20:02:05 -0400 Date: Sun, 23 Jun 91 20:02:05 -0400 From: nacomb@surfer.EPM.ORNL.GOV (NA-NET) Message-Id: <9106240002.AA07167@surfer.EPM.ORNL.GOV> Subject: NA Digest, V. 91, # 25 Apparently-To: ehg@research.att.com NA Digest Sunday, June 23, 1991 Volume 91 : Issue 25 Today's Editor: Cleve Moler Today's Topics: Sparse Matix Eigenvals: Lanczos vs. Householder? Contents: Linear Algebra and Its Applications 2nd ILAS Meeting 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: David Rabson Date: 18 Jun 91 17:21:41 GMT Subject: Sparse Matix Eigenvals: Lanczos vs. Householder? I need to diagonalize some very sparse matrices (density less than 5 per row of at least 1300) and wish very much to avoid fill-in. I had thought that Lanczos would give only the highest and lowest eigenvalues, but recently someone suggested that some modification could tell me whether or not there was an eigenvalue or were eigenvalues in any interval I chose to request. For my purposes, I know that all eigenvalues lie between -5 and +5, and it would suffice to split this range into a few thousand intervals and ask if there were eigenvalue(s) in each such interval. What really interests me is the pattern of intervals with NO eigenvalues. On the other hand, Tewarson (Sparse Matrices, Ch. 7) discusses a pivoting technique applicable to Givens or to Householder tridiagonalization that apparently minimizes fill-in. Does anyone have opinions on the relative merits and disadvantages of these two approaches? Are there public-domain routines available for anonymous FTP? David Rabson Departments of Physics, University of British Columbia and McMaster University rabson@physics.ubc.ca (Internet) DAVIDRA@CRNLASSP (Bitnet) ------------------------------ From: Richard Brualdi Date: Mon, 17 Jun 91 06:54:16 cdt Subject: Contents: Linear Algebra and Its Applications LINEAR ALGEBRA AND ITS APPLICATIONS Table of Contents, Volumes 154-56, Aug-Oct 1991 SPECIAL ISSUE: Iterations in Linear Algebra and Its Applications Special Editors: O. Axelsson, J. de Pillis, M. Neumann, W. Niethammer, and R. J. A. Hadjidimos and A. K. Yeyios (West Lafayette, Indiana) Some Recent Results on the Modified SOR Theory Douglas James (Raleigh, North Carolina) Order-Reducing Conjugate Gradients versus Block AOR for Constrained Least-Squares Problems Josep E. Peris (Alicante, Spain) A New Characterization of Inverse-Positive Matrices Shmuel Friedland (Chicago, Illinois) Revisiting Matrix Squaring Pierre Semal (Louvain-la-Neuve, Belgium) Iterative Algorithms for Large Stochastic Matrices Miron Tismenetsky (Heidelberg, Germany) A Decomposition of Toeplitz Matrices and Optimal Circulant Preconditioning Ananda D. Gunawardena (Houston, Texas), S. K. Jain, and Larry Snyder (Athens, Ohio) Modified Iterative Methods for Consistent Linear Systems Kimon Kontovasilis (Raleigh, North Carolina), Robert J. Plemmons (Winston-Salem, North Carolina), and William J. Stewart (Raleigh, North Carolina) Block Cyclic SOR for Markov Chains with p-Cyclic Infinitesimal Generator Biswa Nath Datta (DeKalb, Illinois) and Youcef Saad (Minneapolis, Minnesota) Arnoldi Methods for Large Sylvester-Like Observer Matrix Equations, and an Associated Algorithm for Partial Spectrum Assignment A. V. Knyazev and A. L. Skorokhodov (Moscow, USSR) Roland Freund (Wu@a2rzburg, Germany) On Polynomial Preconditioning and Asymptotic Convergence Factors for Indefinite Hermitian Matrices Ronald B. Morgan (Columbia, Missouri) Computing Interior Eigenvalues of Large Matrices L. Elsner (Bielefeld, Germany), M. Neumann (Storrs, Connecticut), and B. Vemmer (Bielefeld, Germany) The Effect of the Number of Processors on the Convergence of the Parallel Block Jacobi Method M. Tismenetsky (Haifa, Israel) A New Preconditioning Technique for Solving Large Sparse Linear Systems Gerhard Starke and Wilhelm Niethammer (Karlsruhe, Germany) SOR for AX - XB=C Dianne P. O'Leary (College Park, Maryland) Yet Another Polynomial Preconditioner for the Conjugate Gradient Algorithm Lothar Reichel (Lexington, Kentucky) The Application of Leja Points to Richardson Iteration and Polynomial Preconditioning William F. Trench (San Antonio, Texas) Numerical Solution of the Eigenvalue Problem for Efficiently Structured Hermitian Matrices Yongzhong Song (Nanjing, Peoples' Republic of China) omparisons of Nonnegative Splittings of Matrices Martin Hanke (Karlsruhe, Germany), Michael Neumann (Storrs, Connecticut), and Wilhelm Niethammer (Karlsruhe, Germany) On the Spectrum of the SOR Operator for Symmetric Positive Definite Matrices Wang Deren (Shanghai, Peoples' Republic of China) On the Convergence of the Parallel Multisplitting AOR Algorithm Amit Bhaya, Eugenius Kaszkurewicz, and Francisco Mota (Rio de Janeiro, Brazil) Asynchronous Block-Iterative Methods for Almost Linear Equations Tsun-Zee Mai (Tuscaloosa, Alabama) Composite Adaptive Procedure for Solving Large Sparse Linear Systems Z. Strakos (Praha, Czechoslovakia) On the Real Convergence Rate of the Conjugate Gradient Method J. de Pillis (Riverside, California) A Parallelizable SOR-Like Method: Systems With Plus-Shaped and Linear Spectra Monga-Made Magolu and Yvan Notay (Bruxelles, Belgium) On the Conditioning Analysis of Block Approximate Factorization Methods Alvaro R. De Pierro (Campinas, Brazil) and Alfredo N. Iusem Rio de Janeiro, Brazil) On the Convergence of SOR- and JOR-Type Methods for Convex Linear Complementarity Problems Paul E. Saylor (Zu@a2rich, Switzerland) and Dennis C. Smolarski (Santa Clara, California) Implementation of an Adaptive Algorithm for Richardson's Method I. E. Kaporin (Moscow, USSR), L. Yu. Kolotilina (Leningrad, USSR), and A. Yu. Yeremin (Moscow, USSR) Block SSOR Preconditioning for High-Order 3D FE Systems. II. Incomplete BSSOR Preconditionings Sabine Van Huffel (Heverlee, Belgium) Iterative Algorithms for Computing the Singular Subspace of a Matrix Associated With Its Smallest Singular Values Yvan Notay (Bruxelles, Belgium) Conditioning Analysis of Modified Block Incomplete Factorizations Victor Eijkhout (Urbana, Illinois) Analysis of Parallel Incomplete Point Factorizations Angelika Bunse-Gerstner and Ludwig Elsner (Bielefeld, Germany) Schur Parameter Pencils for the Solution of the Unitary Eigenproblem Ivo Marek (Praha, Czechoslovakia) and Daniel B. Szyld (Philadelphia, Pennsylvania) Pseudoirreducible and Pseudoprimitive Bounded Operators Achiya Dax (Jerusalem, Israel) A Row Relaxation Method for Large I1 Problems Jerome Dancis (College Park, Maryland) The Optimal w Is Not Best for the SOR Iteration Method Special Issues in Progress 1. Algebraic Linear Algebra; special editors are Robert M. Guralnick, William H. Gustafson, and Lawrence S. Levy. To appear as Volume 157, October 15, 1991. 2. Proceedings of the Auburn 1990 Matrix Theory Conference; special editors are David Carlson and Frank Uhlig. Submission deadline: August 1, 1990. Details provided with the conference announcement. 3. Proceedings of the Sixth Haifa Conference on Matrix Theory; special editors are A. Berman, M. Goldberg, and D. Hershkowitz. Submission deadline: October 1, 1990. Details provided with the conference announcement. 4. Proceedings of the International Workshop on Linear Models, Experimental Designs and Related Matrix Theory, (August 6-8, 1990, Tampere, Finland); special editors are Jerzy K. Baksalary and George Styan. Submission deadline: October 31, 1990. Details provided with the conference announcement. 5. Proceedings of the Second NIU Conference on Linear Algebra, Numerical Linear Algebra and Applications, (May 3-5, 1991, Northern Illinois University, DeKalb, Illinois); special editors are Biswa Datta, Robert Plemmons, and Roger Horn. Submission deadline: August 31, 1991. Details provided with the conference announcement. Special issues are available to individuals at a reduced rate. For further infor mation, please contact Bob Biederman, Journals Customer Service, Elsevier Science Publishing Co., 655 Avenue of the Americas, New York, NY 10010; Tel. 212- 633-3 955; Fax 212-633-3990. ------------------------------ Date: Thu, 20 Jun 91 15:44:03 IST From: Danny Hershkowitz Subject: 2nd ILAS Meeting THE SECOND MEETING OF THE INTERNATIONAL LINEAR ALGEBRA SOCIETY August 3-7, 1992 University of Lisbon Portugal FIRST ANNOUNCEMENT The Second Meeting of The International Linear Algebra Society (ILAS) will be held at the University of Lisbon, Portugal, on August 3-7, 1992. There will be about twelve one-hour invited talks and twenty eight half-hour invited talks. Also, we wish to encourage contributed 15-20 minute talks, subject to the unavoidable limitations of space and time. If you are interested in giving a contributed talk at the conference, please send a title and an abstract, to be received by us no later than May 1992. The title and the abstract should be sent to Professor J.A. Dias Da Silva, at the address given below. A special issue of Linear Algebra and its Applications will be devoted to the meeting. This issue will contain only papers that meet the publication standards of the journal, and that are approved by normal refereeing procedures. The issue will also contain synopses of the talks of those invited speakers who do not submit a paper to the proceedings. Special editors of this issue are Professors J.A. Dias Da Silva, Chi-Kwong Li and G.N. de Oliveira. Further information about the conference (when available) will be sent upon request. The organizing Committee of the meeting consists of: CHAIRMAN: Professor J.A. Dias Da Silva Departamento de Matematica da Universidade de Lisboa Rua Ernesto de Vasconcelos, Bloco C1 1700 Lisboa Portugal E-mail address: mperdiga@ptearn.BITNET MEMBERS: Professor David H. Carlson Dept. of Mathematical Sciences College of Sciences San Diego State University San Diego, CA 92182-0314 U.S.A. E-mail address: sdsu!carlson@sdcsvax.ucsd.edu Professor Daniel Hershkowitz Mathematics Department Technion - Israel Institute of Technology Haifa 32000 Israel E-mail address: MAR23AA@TECHNION.BITNET Professor Thomas J. Laffey Mathematics Department University College, Belfield, Dublin, 4, Ireland E-mail address: TLAFFEY@IRLEARN.BITNET Professor G.N. de Oliveira Departamento de Matematica Universidade de Coimbra 3000 Coimbra Portugal Professor Hans Schneider Mathematics Department Van Vleck Hall University of Wisconsin - Madison Madison WI 53706 U.S.A E-mail address: hans@math.wisc.edu ------------------------------ End of NA Digest ************************** -------