**Today's Topics:**

- NA-Net's Expansion
- Congratulations to Joe Traub
- New Book by David Watkins
- Adaptive Mesh Refinement Techniques
- Solution of Block Toeplitz Linear System
- Seeking Recent Version of PITCON
- Sparse Least Square Solvers
- Department Head Position at University of Akron
- International Linear Algebra Society
- Workshop on Analytic, Intelligent and Database Computing

From: Jack Dongarra <dongarra@cs.utk.edu>

Date: Wed, 20 Feb 91 08:10:58 -0500

I happened to be looking at the NA-Net database and came up with

the following data on NA-Net growth since it moved to ORNL.

Individuals reachable thru

na.@na-net.ornl.gov

Dec 90 1592

Jan 91 1679

Feb 91 1851

Jack

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From: Gene Golub <golub@Cholesky.Stanford.EDU>

Date: Fri, 22 Feb 91 16:26:46 PST

Congratulations to Joe Traub for being awarded the Emanuel R.Piore

Award of the IEEE "for pioneering research on algorithms and

computational complexity , parallelism and optimal iteration theory,

and for leadership in computing education."

Gene Golub

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From: David Watkins <WATKINS%WSUMATH.BITNET@CUNYVM.CUNY.EDU>

Date: Mon, 18 Feb 91 08:27 PDT

My book ``Fundamentals of Matrix Computations'' is finally in print.

This book is intended for an upper division or (relatively easy)

graduate course. It attempts less than Golub and Van Loan but spends

more effort on motivation and explanation. If your students have

trouble reading Golub and Van Loan, they might like my book. The

publisher is John Wiley and Sons. The table of contents is listed

below.

David Watkins

Washington State University

1. Gaussian Elimination and its Variants

2. Sensitivity of Linear Systems; Effects of Roundoff Errors

3. Orthogonal Matrices and the Least Squares Problem

4. Eigenvalues and Eigenvectors I

5. Eigenvalues and Eigenvectors II

6. Other Methods for the Symmetric Eigenvalue Problem

7. The Singular Value Decomposition (SVD)

Appendices

A. Fast Rotators

B. Software for Matrix Computations

------------------------------

From: Dan Peterka <dan@scubed.com>

Date: 20 Feb 91 22:31:44 GMT

I need a crash course in Adaptive Mesh Refinement Techniques and would

like some pointers to the definitive works dealing with this subject.

I'd also like to know where I might beg, borrow or steal a Fortran

implementation of AMR to use as a starting point in bootstrapping

myself. I'm particularly interested in methods dealing with

rectangular meshes, but triangular meshes would be OK too.

Thanks for any help...

Dan Peterka S-CUBED 3398 Carmel Mtn Rd.

dan@scubed.com (619) 587-8338 San Diego, CA 92121

------------------------------

From: Chuck Ferrara < adiron!chuck@uunet.uu.net>

Date: 21 Feb 91 14:17:39 GMT

HELP!

I need to implement, in real time, a solution for a real, symmetric, block

toeplitz, linear system. This is used to design optimal matched filters

for 2-D signal processing. I have scene solutions and source code for

op. count estimates or references would be very helpful.

Thanks in advance

Chuck Ferrara uunet!adiron!chuck

PAR Government Systems Corp.

220 Seneca Tpk

New Hartford, NY 13413

(315) 738-0600 X247

------------------------------

From: Roger Alexander <alex@iastate.edu>

Date: 21 Feb 91 18:35:58 GMT

Greetings,

The PITCON code of Rheinboldt and Burkardt, software for

numerical analysis of parametrized nonlinear equations, exists in

several versions. I have the 1981 TOMS version distributed

by IMSL, and am looking for a more recent one.

In Rheinboldt's 1983 lectures at University of Arkansas,

published by Wiley, an Appendix presents a completely rewritten

PITCON. Is this (or something more recent?) available anywhere

in machine-readable form?

Many thanks for any help.

Roger Alexander PING: alex@iastate.edu

Department of Mathematics DING: (515) 294-7579

400 Carver Hall

Iowa State University

Ames, Iowa 50011 USA

------------------------------

From: Tim Monks <tim@bhpmrl.oz.au>

Date: Fri, 15 Feb 91 17:02:41 EST

Hello,

Are there any routines available that will solve least square problems

for rectangular sparse matrices ?

I am trying to solve a regularized least squares problem for Au = b,

where A is non-square, large (typically 16384 x 4096), and sparse.

I am thinking that methods based on QR or SVD factorizations would be

appropriate, as A is not well enough conditioned to solve the normal

equations with LU decomposition. The only routine I have found that

will do this is NAg (F04QAF) which is based on the TOMS Alg. 583 LSQR

by Paige & Saunders. This solves either the least square or a damped

least squares problem (ridge regression) using a Lanczos algorithm. It

uses reverse communication to calculate requisite matrix-vector

products. I haven't got LSQR out of netlib (yet) so I can't say how it

will work.

I have looked elsewhere for relevant routines. Generally I've found that

the routines exist, but require full storage and are generally for dense

matrices. The sparse libraries are usually restricted to square,

generally symmetric matrices.

So - are there any sparse routines available to solve least squares

problems ?

If not, what methods would you recommend to solve this type of problem ?

I have read Censor's row-action paper, but would prefer a column-

generation method as this suits my problem much better. I have

tried Gauss-Seidel & SOR on both the unregularised, and a regularized

objective, but have not had much success. Any pointers would be

appreciated.

Here is a summary of the libraries I have heard about, or looked at -

none appear to be satisfactory for the job. Those marked (?) are those

I am not sure about.

FULL STORAGE

Linpack - (DQRDC, DQRSL) QR factor & LS solve.

IMSL - (LQRRR & LSQRR) same routine

Classpack - (KDQRDC & KDQRSL) same routine

NAPACK - QR, OVER

Vanhuffel - Total least squares solution to Ax=b, A any size.

SPARSE STORAGE

Harwell MA28 - LU factorisation only

ITPACK 2C - Symmetric PD. CG.

ITPACK 3A - CG and Orthomin variants. Overdetermined ?

ITPACK NSPCG - ???

MADPACK - A nxn. Multigrid Gaussian elimination, Gauss-Seidel, Orthomin.

NSWC library - (SPSLV) LU factorisation only.

PORT - LU factorisation + algebra ?

SGE - Gaussian elimination

SLAP - A nxn. CG

SPARSEPAK - Direct methods ?

Sparse1.3 - LU factorisation only

Yale - Direct methods ??

pcgpack - ?

y12m - ?

Dr. Tim Monks

Image Processing & Data Analysis Group | (direct) (+61-3)566-7448

BHP Research - Melbourne Laboratories | (switch) (+61-3)560-7066

245 Wellington Rd, Mulgrave, 3170, | (fax) (+61-3)561-6709

AUSTRALIA | (EMAIL) tim@bhpmrl.oz.au

------------------------------

From: S. I. Hariharan <hari@zippysun.math.uakron.edu>

Date: Wed, 20 Feb 91 19:04:30 EST

THE UNIVERSITY OF AKRON

HEAD - DEPARTMENT OF MATHEMATICAL SCIENCES

The Department of Mathematical Sciences invites applications and

nominations for the position of department head. A PhD in the mathematical

sciences (mathematics, applied mathematics, statistics, or computer science)

and a strong commitment to teaching and research are required. Some

administrative and/or professional experience in a mathematical sciences

PhD program is desirable. The Department consists of thirty-seven full-time

faculty members and offers BS degrees in mathematics, applied mathematics,

statistics, and computer science, and MS degrees in mathematics,

applied mathematics, and statistics. The department has proposed graduate

programs for the MS in Computer Science, and the PhD in Applied Mathematics.

The University of Akron is the third largest state university in

Ohio (30,000 day and evening students) and offers a multitude of associate,

bachelors, masters, and doctorate degree programs in the physical and

social sciences, engineering, and education.

Review of applications will begin April 15, 1991 and continue until

the position is filled. Tentative inquiries are desirable and will be treated

confidentially. Please send a curriculum vita and names of at least three

references to: Dr. Chand Midha, Chair, Search Committee, Department of

Mathematical Sciences, The University of Akron, Akron, OH 44325-4002

(Email: R1CM@AKRONVM.BITNET

Phone: (216)-972-7128/7400).

The University of Akron is an equal opportunity/affirmative action employer.

Women and minorities are encouraged to apply.

------------------------------

From: Danny Hershkowitz <MAR23AA%TECHNION@TAUNIVM.TAU.AC.IL>

Date: Wed, 20 Feb 91 22:00:02 IST

THE INTERNATIONAL LINEAR ALGEBRA SOCIETY ( ILAS )

E-mail Address: MAR23AA @ TECHNION (bitnet)

Edited by Danny Hershkowitz

20 February 1991

ILAS-NET Message No. 104

CONTRIBUTED ANNOUNCEMENT:

FROM: Charlie Johnson

SUBJECT: REU Program

SUMMER RESEARCH FELLOWSHIPS for UNDERGRADUATES

We are pleased to announce that we have again been selected by the National

Science Foundation (NSF) as one of a few nation-wide sites to offer funded

research experiences for undergraduates (REU) in the summer of 1991. The

theme of our summer research program is Matrix Analysis and Applications.

The predominant objective is to provide talented students with experience

at how mathematics is done in contrast to the deducive fashion in which it

is normally taught.

We are soliciting applications from undergraduate students who will not

graduate prior to June 1991 both within our geographical region and across

the nation. At least eight students will be selected on a competitive basis.

Each student will receive approximately $2400 ($2000 stipend plus $400

toward subsistence) and free housing in one of the College's residence

halls.

The NSF-REU program will be conducted from June 17 to August 9. Each

student will select a topic in matrix analysis and a primary advisor with

whom to work. The first week of the program will contain a series of

background lectures to establish a common language for the entire program

and to advance students to an appreciation of certain "open" (yet accessible)

problem areas. A computer laboratory consisting of tem 80386 class

personal computers and computer software such as MATLAB and MATHEMATICA

will be available to aid in mathematical exploration. In addition students

will gain a sense of the environments in which pure and applied mathematics

is carried out. Specifically, visits are planned to NASA/Langley Research

Center, ICASE, VIMS (Virgina Institute of Marine Science", CEBAF (Continuous

Electronic Beam Accelerator Facility), and NIST (formerly the National

Bureau of Standards).

To apply: Send a letter containing the following (a) a statement of your

interest in mathematics and (b) a description of the mathematics courses

(e.g., textbook titles) you have completed as well as the grades received.

Also, please arrange to have two letters of recommendation sent from

mathematics instructors and/or any other person(s) who are best qualified

to comment on your mathematical ability and experience. Send all application

material to Professor George T. Rublein at:

Department of Mathematics

The College of William & Mary

Williamsburg, VA 23187-8795

Please send all materials by March 16, 1991. If you have any questions or

need more information, please contact Professor Rublein by mail, telephone

(804)221-2028, or bitnet GTRUBL@WMVM1. You may also contact Charles

Johnson for questions.

------------------------------

From: Bob Grossman <grossman@wagner.lac.math.uic.edu>

Date: Thu, 21 Feb 91 17:43:55 CST

The NASA Ames - University of Illinois at Chicago

Symposia in Computation and Control 91

New Directions in Computing:

Analytic, Intelligent and Database Computing

University of Illinois at Chicago

April 7 and 8, 1991

Traditionally, computers have been used for numerical

simulations of physical processes, while the modeling

and analysis were done off line. Today computers are

used not only for numerical studies, but also to derive

better models, more accurate algorithms, and to automate

many of the computations that were formerly done by hand.

This conference will explore three areas: analytic

computing, or the application of symbolic and numeric

algorithms to nonlinear systems; intelligent computing,

or combining symbolic and numeric techniques with methods

incorporating knowledege of science and mathematics; and

database computing, or using databases as an integral

part of the computing environment. The speakers are:

Hal Abelson, MIT

"Intelligence in Scientific Computing"

Robert Grossman, University of Illinois at Chicago

"Analytic Computing"

John Guckenheimer, Cornell University

"Computing and Dynamical Systems"

Leo Joskowicz, IBM T. J. Watson Laboratory and

Elisha Sacks, Princeton University

"Automating Scientific and Engineering Reasoning"

Jack A. Orenstein, Object Design Inc.

"Object Oriented Databases"

Arie Shoshani, Lawrence Berkeley Laboratory

"Scientific Databases"

Richard Zippel, Cornell University

"Integrating Numeric and Symbolic Computing"

The workshop is sponsored by: NASA Ames; The Software Technologies

Program at the University of Illinois at Chicago; and the

Laboratory for Advanced Computing at the University of Illinois at Chicago.

To register, contact: Dr. Winifred Lyday, Software Technologies

Research Center, University of Illinois at Chicago, Mail Code 454,

Suite 226, 2201 West Campbell Park Drive, Chicago, IL 60612,

phone: (312) 996-5203, fax: (312) 413-3029,

email: scc91@wagner.lac.math.uic.edu.

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End of NA Digest

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