### Today's Editor:

- Cleve Moler
- The MathWorks, Inc.
- moler@mathworks.com

- Fast Hartley Transform
- Mesh Generation Bibliography
- Who Solves ODEs of the form y''=f(x,y)?
- Three Dimensional Singular Elements
- Temporary Change of Address for Jim Bunch
- New Jersey Section of SIAM Spring Meeting
- Conference on Approximation and Probability
- 35th British Theoretical Mechanics Colloquium
- Parlett-Kahan Meeting
- XI Parallel Circus
- Positions at University of Vermont
- Visiting Positions at Arizona State
- Contents: SIAM Scientific and Statistical Computing

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

From: David H. Bailey <dbailey@nas.nasa.gov>

Date: Thu, 19 Mar 92 09:26:00 -0800

**Subject: Fast Hartley Transform**

Readers of the NA Net Digest may have noted the recent posting of a

seminar on the Hartley transform.

It is widely believed, and sometimes stated or implied in print, that

for purely real inputs the fast Hartley transform (FHT) is twice as

fast as the fast Fourier transform (FFT), since the FHT operates with

real data instead of complex data.

However, there exist well-known variants of the FFT that compute the

discrete Fourier transform (DFT) on real input data in only half the

operations required for the standard complex FFT. One way is to

employ formulas that convert an FFT on real input data into a complex

FFT of half the size. An even more efficient scheme is to use Edson's

algorithm, which computes the DFT result using real arithmetic, and

which does not require a pre- or post-processing step. Almost all

vendor FFT libraries include efficient implementations of such

schemes, and these routines usually run faster than implementations of

the FHT.

Thus the FHT is not fundamentally more efficient than well-known

variants of the FFT, even for real data, and the Hartley transform

itself has no known physical significance. Also, the FHT software as

developed at Stanford is patented, and commercial usage requires

consent from Stanford.

In summary, we frankly do not understand the continuing interest in

the FHT. Can anyone offer solid scientific reasons for using the FHT

in place of the real-to-half complex FFT?

David H. Bailey, NASA Ames

Paul N. Swarztrauber, NCAR

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

From: Stephen Vavasis <vavasis@cs.cornell.edu>

Date: Mon, 23 Mar 92 14:43:48 -0500

**Subject: Mesh Generation Bibliography**

Over two years ago in this forum I posted a notice that I was

interested in writing a bibliography on automatic mesh generation for

finite elements. The task quickly overwhelmed me, and I never

finished it.

The good news is that Marshall Bern of Xerox PARC and David Eppstein

of U.C. Irvine have written a very nice illustrated summary of

automatic mesh generation. Their summary is in the form of an

annotated book chapter, and is also available as a Xerox technical

report. The summary looks at the problem primarily from the computer

science viewpoint (rather than from the applications viewpoint).

The title of the report is "Mesh Generation and Optimal

Triangulation"; if you are interested please contact Marshall Bern

directly: bern@parc.xerox.com.

-- Steve Vavasis

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

From: John Coleman <John.Coleman@durham.ac.uk>

Date: Thu, 26 Mar 92 15:30:57 GMT

**Subject: Who Solves ODEs of the form y''=f(x,y)?**

I would like to hear from you if you solve second-order differential

equations of the special form y''=f(x,y), where y and f may be vectors, or

if you know of anyone who does.

Many numerical methods have been proposed for these equations, in papers

which may contain one or two simple problems for which method n+1 is 'better'

than method n. I would like to make contact with people who solve such

problems to find an answer rather than to test a method. I am particularly

interested in the sub-class of problems having oscillatory solutions --

such as orbit problems in classical mechanics, quantum mechanical scattering

problems governed by the radial Schrodinger equation, and perhaps others

about which I know nothing.

In your response please tell me:

(a) the form and the origin of the problem,

(b) the numerical method or methods currently used,

(c) the accuracy required and how you know if you have got it,

(d) what difficulties (if any) arise in the solution process,

(e) how satisfactory you consider your present approach to be,

(f) any relevant references.

I believe that the information I seek would be of interest to several people

involved in the numerical analysis of ODEs. If I get a good response I intend

to submit a summary to the NA Digest.

My thanks in advance to all who can contribute in any way.

John Coleman.

E-mail: John.Coleman @ durham.ac.uk

na.jcoleman @ na-net.ornl.gov

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

From: E.V.Glushkov <evg@kgu.kuban.su>

Date: 26 Mar 92 16:02:58 GMT

**Subject: Three Dimensional Singular Elements**

Hello from Russia,

As is well-known, use of so-called singular elements

in a 2-dim. finite element method improves the convergence

and accuracy very much. But it is very difficult to find the

order of singularity at the 3-dim. corner points, and therefore

to construct the singular elements.

In our lab there was eleborated, realized as a computer

program and tested a method of the singularity orders at a top

of an arbitrary elastic polihedron extracting. The method is

based on the spectral points of some integral operators seaching.

We are not specialists in FEM and, being restricted in our com-

puter's output, cannot carry out a regular and thorough numerical

analysis. Untill now we've obtained results for a top of a cube

with one fixed side and for some other geometries.

So, if somebody is interested in employing 3-dim. singularities,

please contact us and we'll discuss how a co-operation could be

arranged.

Sincerely,

Drs. E.V.Glushkov & N.V.Glushkova E-mail: evg@kgu.kuban.su

Kuban State University

Institute of Mechanics and

Applied Mathematics

Krasnodar 350640, Russia

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

From: James R. Bunch <jrb@sdna3.ucsd.edu>

Date: Thu, 26 Mar 92 11:53:23 -0800

**Subject: Temporary Change of Address for Jim Bunch**

I will be at the IMA during April 3 - June 6, 1992:

Prof. James R. Bunch

IMA, Univ. of Minnesota

514 Vincent Hall

206 Church St SE

Minneapolis, MN 55455-0436

bunch@ima.umn.edu

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

From: SIAM <ddilisi@siam.org>

Date: Tue, 24 Mar 92 10:25:37 EST

**Subject: New Jersey Section of SIAM Spring Meeting**

New Jersey Section of SIAM: Spring Meeting

The spring meeting of the New Jersey Section of SIAM will be held

on Saturday morning, April 25, 1992 from 8:30 to noon. It will

be held on the Busch Campus of Rutgers University in Piscataway.

There will be two distinguished speakers who will provide an

excellent mix of applied mathematics and computer science:

o Diane Souvaine of the Computer Science Department and

DIMACS, Rutgers University, on "Finding Maximum Inscribed

Triangles and Shortest Aquarium Keeper Tours Using Shortest

Paths."

o Bruce L. Bush of the Molecular Systems Department, Merck

Research Laboratories, Rahway, NJ, on "Some Headaches in

Biomolecular Modeling: Are Mathematical Remedies on the

Shelf?"

Mathematicians in industry are encouraged to attend the meeting.

The meeting will provide a unique opportunity for applied

mathematicians in local industries, research laboratories, and

academic institutions to meet and share problems, methods, and

solutions. The meeting is not only for SIAM members but is open

to all interested people. You are encouraged to bring along your

colleagues. Graduate and undergraduate students are most

welcome.

For a copy of the schedule of the meeting, titles and abstracts

of the talks, and detailed directions, send your mailing address

and request for same to siam@siam.org.

Richard B. Pelz

President, New Jersey Section of SIAM

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

From: George Anastassiou <ANASTASG@hermes.msci.memst.edu>

Date: 24 Mar 92 16:54:59 CDT

**Subject: Conference on Approximation and Probability**

The following is of concern primarily to approximation theory and

probability people, but some people from numerical analysis might

be interested.

An international conference on "Approximation,Probability & Related Fields"

Place: Univ. California at Santa Barbara

Dates: 20,21,22 May 1993

Days: Thurs.,Friday,Saturday

Information-Organizers:

George Anastassiou

Dept. Mathematical Sciences

Memphis State University

Memphis TN 38152

E-mail anastasg@hermes.msci.memst.edu

S.T.Rachev

Dept. Statistics & Applied probability program

University of california at Santa Barbara

Santa Barbara CA 93106 U.S.A

E-mail ZARIRACH@BERNOULLI.UCSB.EDU

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

From: D. Sloan <CAAS10@vaxb.strathclyde.ac.uk>

Date: Thu, 26 Mar 92 10:47 GMT

**Subject: 35th British Theoretical Mechanics Colloquium**

BRITISH APPLIED MATHEMATICS COLLOQUIUM

35th British Theoretical Mechanics Colloquium

5th - 8th April 1993

Venue: University of Strathclyde in Glasgow

Start Time: Approx. 4.00pm on Monday 5th April 1993

Finish Time: Lunch on Thursday 8th April 1993

Invited Speakers

Computational Mathematics

Professor Bengt Fornberg (Exxon Corporate Research, NJ, USA

& University of Strathclyde)

Mathematical Biology

Professor Bob May, FRS (University of Oxford)

Solid Mechanics

Professor Ingo Muller (Technische Universitat Berlin)

Differential Equations

Professor Larry Payne (Cornell University)

Rheology

Professor Ken Walters, FRS (University College of Wales, Aberystwyth)

Stewartson Memorial Lecture

Professor Alex Craik (University of St Andrews)

Mini- Symposia

Liquid Crystals Industrial Mathematics

Inverse Problems Nonlinear Dynamical Systems

Office Bearers

Chairman Professor Frank Leslie Tel: 041 552 4400 EXT 3655

Secretary Dr. Ian Murdoch Tel: 041 552 4400 EXT 3657

Treasurer Dr. John Parkes Tel: 041 552 4400 EXT 3720

E-mail address bamc93@uk.ac.strath

Postal Address:

British Applied Mathematics Colloquium

Department of Mathematics

University of Strathclyde

Glasgow G1 1XH

U. K.

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

From: James R. Bunch <jrb@sdna3.ucsd.edu>

Date: Thu, 26 Mar 92 12:04:13 -0800

**Subject: Parlett-Kahan Meeting**

SECOND ANNOUNCEMENT

THREE DECADES OF NUMERICAL LINEAR ALGEBRA AT BERKELEY:

A CONFERENCE IN HONOR OF THE SIXTIETH BIRTHDAYS

OF BERESFORD PARLETT AND WILLIAM KAHAN

A conference will be held at MSRI in Berkeley on Saturday, October 17,

1992, in honor of the 60th birthdays of Beresford Parlett and William Kahan.

The Organizing Committee consists of:

James Bunch, UC San Diego, jbunch@ucsd.edu (March 28-midJune: bunch@ima.umn.edu)James Demmel, UC Berkeley, demmel@imafs.ima.umn.edu (after midJune: demmel@

wsparc.berkeley.edu)

Horst Simon, NASA Ames, simon@nas.nasa.gov

The speakers at the conference will be:

Scott Baden, UC San Diego

James Bunch, UC San Diego

James Demmel, UC Berkeley

Gene Golub, Stanford

Anne Greenbaum, Courant

Larry Nazareth, Washington State

Bahram Nour-Omid, San Francisco

John Reid, Rutherford Appleton Laboratory, England

David Scott, Intel

G. W. Stewart, Maryland

Peter Tang, Argonne

There will be a banquet on the evening of October 17. The banquet

speaker will be Richard Lau, ONR.

There will be a Special Issue of the Journal of Numerical Linear Algebra

with Applications dedicated to Parlett and Kahan. The deadline for manuscripts

will be October 17, 1992. James Bunch will be the editor of the Special Issue.

Anyone interested in submitting a manuscript should obtain a copy of

"Guidelines for Contributors" from James Bunch.

HOTEL INFORMATION: We have been able to reserve only 40 rooms for the

conference. Some other departments are having conferences that same weekend.

You must make your own reservation directly with the hotel, but mention the

conference.

20 single rooms reserved: Durant Hotel, 2600 Durant Ave, Berkeley 94704;

at the campus; 510-845-8981. $75/single. (Only singles are available.)

20 rooms reserved: Marriott Hotel, 200 Marina Blvd., Berkeley; at the

Berkeley Marina, 1 1/2 miles from campus, city bus service is convenient.

510-548-7920. $85 flat rate per room for a single double, triple, or quad.

Other possibilities:

The Women's Faculty Club, 510-642-4175, on campus.

The Men's Faculty Club, 510-642-1993, on campus.

The Shattuck Hotel, 510-845-7300, downtown Berkeley. (They weren't willing to

reserve a block of rooms.)

There are various motels in the area. We will get a list later.

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

From: Gene Golub <golub@a31.ima.umn.edu>

Date: Thu, 26 Mar 92 20:52:42 CST

**Subject: XI Parallel Circus**

XIth Parallel Circus

sponsored by the Department of Computer Science, Cray Research, Inc.,

and the Minnesota Supercomputer Institute April 24-25, 1992

The Department of Computer Science, Cray Research, Inc., and the

Minnesota Supercomputer Institute, continuing the tradition started at

Yale University in 1986, will be hosting the XIth Parallel Circus at

the Minnesota Supercomputer Institute in Minneapolis, MN on Friday and

Saturday, April 24-25, 1992.

The Parallel Circus is an informal meeting which emphasizes parallel

algorithms for scientific computing. There is no set agenda. At the

beginning of each session the attendees reach a consensus as to each

day's program of presentations. This format allows attendees to

discuss the very latest results as well as interesting work in

progress. (The Tenth Circus is described in the NA Digest, v 92, # 10,

March 8, 1992.)

Graduate students are especially welcome to attend.

There is modest support from the National Science Foundation for

student travel to the Parallel Circus XI. Those students requesting

support should give reasons for attending the meeting, and a budget

for expenses. The student(s) should indicate their research interests

and plans. A letter verifying that the student is in good standing

should be sent independently by a faculty adviser. This letter should

give the student's GPA. We will be pleased to consider joint

proposals which would include the expenses of several students.

The dealine for application has been extended to April 1, 1992.

Correspondence by e-mail is desirable.

FAX: (612) 625-0572 (Write "Student Support" on Fax.)

E-mail: circus92@cs.umn.edu

REGISTRATION

To register for XIth Parallel Circus, contact:

Michael Olesen Symposium Administrator Minnesota Supercomputer

Institute 1200 Washington Avenue South Minneapolis, MN 55415

Tel: (612) 624-1356 FAX: (612) 624-8861

e-mail: mikeo@s1.msi.edu.umn

The registration fee of $25 includes lunches on both days of the

symposium as well as a banquet the evening of Friday, April 24, 1992.

Registration is required by April 10, 1992. Post deadline

registrations will be accepted on a space available basis.

TRANSPORTATION

Special conference airfares are available through Daisy Travel of St.

Paul, MN. For details or to make reservations call toll free (800)

553-1660 (8:00 a.m. to 4:30 p.m. CST) and mention that you are

participating in the XIth Parallel Circus at the Minnesota

Supercomputer Institute.

ACCOMMODATIONS

Arrangements have been made for a block of discount rooms at the Days

Inn University, 2407 niversity Avenue S.E., Minneapolis, MN 55414,

for April 23, 24, and 25. The price per night is $39 for single

occupancy and $45 for double. To receive these rates contact them at

(612) 623-3999 and mention that you are participating in the XIth

Parallel Circus at the Minnesota Supercomputer Institute.

PRESENTATIONS

Each presentation will be about 30 minutes long, 25 minutes plus 5

minutes for questions and discussions. Their actual length will

depend on the number of participants wishing to make presentations.

The Circus will begin on Friday morning at 9:00 a.m. Although the

program is not yet set, it will probably conclude early Saturday

afternoon.

Organizers: Gene Golub, Bill Harrad, Ahmed Sameh, Apostolos Gerasoulis

Local Committee: Don Truhlar, Michael Olesen

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

From: U. Vermont <zwick@hal.uvm.edu>

Date: Thu, 26 Mar 92 22:08:07 GMT

**Subject: Positions at University of Vermont**

TWO TENURE TRACK ASSISTANT PROFESSOR POSITIONS IN

COMPUTER SCIENCE

THE UNIVERSITY OF VERMONT

BURLINGTON, VERMONT

Applications are invited for two tenure-track faculty positions in Computer

Science at the level of Assistant Professor beginning in the l992-93 academic

year. Responsibilities will include instruction in mainstream computer

science and the development of a quality research program. Candidates should

show promise of excellence in both teaching and research; have demonstrable

expertise in networks and distributed systems, parallel algorithms and

systems, or database and knowledge base systems; and have a strong interest in

interdisciplinary research in the mathematical sciences. Faculty are

encouraged to supervise graduate students in related fields as well as in

computer science. A doctorate in computer science or a closely related field

is required.

Applications will be accepted until the positions are filled. Please submit

resume and description of current research interests, and have three letters

of recommendation sent directly to Dr. Richard Foote, Search Committee

Chairperson, 101 Votey Building, College of Engineering & Mathematics,

University of Vermont, Burlington, VT 05405. Inquiries may be made by mail to

the above address or by email to cssrch@uvm.edu.

The University of Vermont is an Affirmative Action/Equal Opportunity employer

and encourages applications from women and members of minority groups.

ENDOWED CHAIR POSITION IN

COMPUTER SCIENCE

THE UNIVERSITY OF VERMONT

BURLINGTON, VERMONT

Applications are sought in Computer Science for the Dorothean Chair in the

College of Engineering and Mathematics beginning in the 1992-93 academic year.

It is anticipated that the position will be filled at the level of Full

Professor. The successful candidate is expected to assume a leadership role,

teach mainstream computer science, and develop an externally funded research

program. An established record of excellence in teaching and research in

computer science is required. Candidates should have demonstrable expertise

in networks and distributed systems, database and knowledge base systems, or

parallel algorithms and systems, together with a strong interest in

interdisciplinary research in the mathematical sciences. Faculty are

encouraged to supervise graduate students in related fields as well as in

computer science. A doctorate in computer science or a closely related field

is required.

Applications will be accepted until the position is filled. Please submit

resume and description of current research interests, and have three letters

of recommendation sent directly to Dorothean Search Committee, 101 Votey

Building, College of Engineering & Mathematics, University of Vermont,

Burlington, VT 05405. Inquiries may be made by mail to the above address or

by email to dorsrch@uvm.edu.

The University of Vermont is an Affirmative Action/Equal Opportunity employer

and encourages applications from women and members of minority groups.

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

From: Hans Mittelmann <beck@plato.la.asu.edu>

Date: Thu, 26 Mar 92 17:15:20 mst

**Subject: Visiting Positions at Arizona State**

VISITING POSITIONS AT ARIZONA STATE UNIVERSITY

There is some chance that the Department of Mathematics at Arizona

State University may be able to support one or more visiting

faculty for the 1992/93 academic year (8/16/92-5/15/93). While

these visitors are needed to cover the department's teaching obli-

gations and probably will teach 3-4 courses during the year,

preference will be given to those candidates that contribute also

to the department's research efforts.

In particular, anyone interested in cooperation with members of

the Computational Mathematics Group (Feldstein, Jackiewicz,

Mittelmann, Ringhofer, Welfert; Renaut will be on leave) should

send their vita to my attention. By e-mail (TeX, LaTeX, ASCII):

na.mittelmann or mittelmann@math.la.asu.edu

or by FAX (602) 965 8119.

Hans D. Mittelmann

Department of Mathematics

Arizona State University

Tempe, AZ 85287-1804

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

From: Beth Gallagher <gallaghe@siam.org>

Date: Mon, 23 Mar 92 12:22:15 EST

**Subject: Contents: SIAM Scientific and Statistical Computing**

CONTENTS

SIAM Journal on Scientific and Statistical Computing

July 1992 Volume 13, Number 4

Parallel Methods for Solving Nonlinear Block Bordered Systems of Equations

Xiaodong Zhang, Richard H. Byrd, and Robert B. Schnabel

Solution of Structured Geomotric Programs in Sample Survey Design

Faiz A. Al-Khayyal, Thom J. Hodgson, Grant D. Capps, James A. Dorsch,

David A. Kriegman, and Paul D. Pavnica

An Efficient Scheme for Unsteady Flow Past an Object with Boundary

Conformal to a Circle

Mo-Hong Chou

Block M-Matrices and Computation of Invariant Tori

Luca Dieci and Jens Lorenz

Analysis of Initial Transient Deletion for Parallel Steady-State Simulations

Peter W. Glynn and Philip Heidelberger

An Implementation of the Fast Multipole Method without Multipoles

Christopher R. Anderson

On the Spectrum of a Family of Preconditioned Block Toeplitz Matrices

Takang Ku and C.-C. Jay Kuo

Domain Decomposition with Local Mesh Refinement

William D. Gropp and David E. Keyes

An O(n log n) Time Algorithm for the Minmax Angle Triangulation

Herbert Edelsbrunner, Tiow Seng Tan, and Roman Waupotitsch

Which Cubic Spline Should One Use?

R. K. Beatson and E. Chacko

Integrating Products of B-Splines

A. H. Vermeulen, R. H. Bartels, and G. R. Heppler

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

End of NA Digest

**************************

-------