NA Digest Sunday, December 6, 1992 Volume 92 : Issue 46

Today's Editor:

Cleve Moler
The MathWorks, Inc.

Submissions for NA Digest:

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Information about NA-NET:

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From: Francois Robert <>
Date: Mon, 30 Nov 1992 16:36:28 +0100
Subject: A Proposal for a Fast QR Algorithm

My 92-93 students had a "brillant" idea for the QR algorithm
for eigenvalues of a matrix A:

Instead of iterating the standard (QR factorization, followed by a RQ
computation) they suggest:

* Square A p times: you get A to the power k= 2**p
* Then, factorize into QR
* then, compute A(k+1) = Qtransposed*A*Q

This procedure saves much computational time. However there is a problem with
the squaring. It is quite possible to normalize (just as for the power method)
This normalization does not change Q

Finally my students tested the following procedure:

1) Perform the process with p=4. You get A(16)
2) Iterate the whole process with A(16): Then you can follow the evolution.

On examples with n = 10, they saved half the computational time or more.
The shift process remains unchanged.

Did you hear somewhere of this quite natural method?

Thanks for your help,
"THE CAL'MAT' (calcul matriciel) GROUP" (Lionel CHAILAN, Emmanuel FOLLET
et al., driven by,

Francois ROBERT F. ROBERT ENSIMAG, BP 53X F-38041 Grenoble Cedex Tel. (33) 76 51 47 15


From: Rosie Renaut <>
Date: Mon, 30 Nov 1992 11:51:42 -0700
Subject: Medical Imaging Algorithms (Tomography)

We are looking for recent algorithms for the solution of the following

Given two images f(x,y,z), g(x,y,z) of the same object it is known that one can
be obtained from the other by rotation and translation. Suppose that there
exist angles (ax,ay,az) and displacements (dx,dy,dz) and a scalar s such
that f is obtained from g by the rotations, displacements and scalar multiplying
factor. What is the most effective way to find these 7 parameters?

Comments on parallel implementations for the solution of this problem
also useful


Replies to: (Qing He)


From: Wojciech Owczarz <>
Date: Thu, 3 Dec 92 11:37:45 CET
Subject: Workstations for a Blind Numerical Analyst

I am implementing the numerical analysis software. I am blind and
work with several mainframe systems by using my PC with vista-card
plus sound. I want to use a workstation, therefore I am looking for
a contact with another blind numerical analyst who has experience
with X-windows on a workstation, ideally working with the implemen-
tation of packages for numerical computation.

Wojciech Owczarz
The Danish Computer Center
for Research and Education (UNI-C)
DTH, Bldg. 305
DK-2800 Lyngby, Denmark
Tel: +45 42 88 39 99 + (after the tone) 2406
Fax: +45 45 93 02 20


From: Nancy Nichols <>
Date: 3rd December 1992 18:46:28 GMT
Subject: Leslie Fox Prize


This year the Leslie Fox Prize Competition meeting is to be held in conjunction
with a special symposium to honour the memory of Leslie Fox and to celebrate
his many important contributions to numerical analysis and the numerical
analysis community. The combined Leslie Fox Prize Meeting and Honorary Sympos-
ium are to be held in Oxford on the 24th and 25th June, 1993. At this time,
entires for the Fox Prize Competition are being invited. Further information
concerning the full two-day meeting will be published at a later date.

Entries for the Sixth Leslie Fox Prize Competition are now being accepted.
Any person who is less that 31 years old on January 1, 1993, and has not
already won a first prize is eligible. Each entry should consist of three
copies of a paper, describing some of the candidate's research, that is
suitable for a 40 minute lecture at a numerical analysis symposium. Whether
or not the work has been published or accepted for publication is irrelevant,
but no person may submit more that one paper. Unsuccessful candidates from
previous competitions are encouraged to enter.

The entries will be considered by an Adjudicating Committee. The Committee
for the Sixth Prize Competition are: Dr Nancy Nichols (Reading, chairman)
Professor Charles Elliott (Sussex) and Professor Christopher Baker (Manchester)

Particular attention will be given to the originality and quality of each paper
and to the suitability of the material for a 40 minute talk to a general
audience of numerical analysts. Papers will be selected by the Committee for
presentation at the Leslie Fox Prize meeting. Only the papers that are
presented at the meeting will be eligible for awards, but, subject to this
restriction the Adjudicating Committee may award any number of first and
secondary prizes.

Entries for the Competition should be received by the chairman by
FEBRUARY 1, 1993. Please note that because of the change in dates of the
meeting, the entry date has been extended by two months.

Each candidate should include a statement of his/her date of birth and should
indicate that he/she would be available to present his/her paper at the
symposium. A joint paper may be submitted by an individual candidate if
accompanied by a statement from the co-authors agreeing to the submission
and detailing the candidate's contribution to the paper. Travel funds
are not generally provided to assist candidates who attend the symposium.

The prizes are derived from a capital fund to which DONATIONS would be
gratefully received at any time. It is a registered non-profit fund, so that
US citizens can claim tax exemption and UK contributors can covenant the
money enabling reclaim of UK tax by the fund. Anyone wishing to contribute
to the fund should contact Nancy Nichols at the address below. Alternatively,
contributions can be sent to the Institute of Mathematics and its Applications,
Southend-on-Sea, UK, which can provide covenant forms.

In this year of Leslie's death we are making a special effort to put the
Prize Fund on a sound financial footing, to ensure its continuation into
the future. We are therefore asking Leslie's friends and colleagues to
consider making a special contribution to the Fund in his honour.
Leslie's wife Clemency is taking a special interest in the survival of the
Prize Fund, and if anyone wishes to make a donation as a memorial, we shall
be pleased to notify her that a gift has been made to the Fund.

Nancy Nichols Tel. +44-734-318988
Department of Mathematics Fax. +44-734-313423
University of Reading email:
Box 220
Reading Berks RG6 2AX


From: Michael Monagan <>
Date: Mon, 30 Nov 92 12:14:08 +0100
Subject: Maple V Release 2

Announcement of Maple V Release 2

Maple V Release 2 is available for Sun 4/SPARC and DEC Unix systems.
We expect to complete ports to other Unix platforms by year end,
and availability on other platforms will follow in the new year.

Release 2 incorporates a completely new user interface and many
new graphical capabilities. The nicest feature of the new interface
is the high quality output of formulae in true mathematical notation.

The new graphical capabilities include contour plots, implicit
plots (2D and 3D), vector plots (2D and 3D), animation (2D and 3D),
and basic support for text, polygons, color, lighting, etc.

Maple, Maple V Release 2 also includes many new and improved
mathematical capabilities. A focus of this version has been given
to fixing bugs, fixing design problems, and to improving the
numerical capabilities, in particular, complex numeric arithmetic,
numerical linear algebra, and numerical solutions to polynomials.

A LaTeX document detailing the new facilities and improvements,
with examples in Maple V Release 2, can be obtained from the Maple
share library using anonymous ftp from
or Get the file summary.tex from the directory
maple/5.0/tex and the style files.

Inquiries about Release 2 should be addressed to

Waterloo Maple Software,
160 Columbia Street West, Waterloo, Ontario,
Canada, N2L 3L3

Phone: (519) 747-2373
FAX: (519) 747-5284


From: Tom Coleman <>
Date: Tue, 1 Dec 92 11:26:56 -0500
Subject: Postdocs at Cornell

Postdoctoral Fellowships

The Cornell Theory Center invites applications for postdoctoral fellowships
in the computational sciences. Fellows will be expected to work with a
faculty mentor and applications should designate a prospective mentor, if

The Cornell Theory Center contains one of four National Science Foundation
Supercomputing facilities. The Center operates several high performance
computers, including an IBM ES-9000, an IBM Power Visualization System, a
cluster of IBM RS-6000 workstations, and a Kendall Square KSR-1 computer.
An Intel iPSC/860 and Thinking Machines Connection Machine CM200 are
operated by the Cornell Computer Science Department. The Theory Center is
also the parent organization for the Advanced Computing Research Institute,
a research group with an emphasis on parallel computation and with close
ties to the Computer Science Department.

We invite applicants interested in all aspects of computational science and

Applications and supporting letters of reference should be sent to J. Addy,
Personnel Manager, Cornell Theory Center, 529 Engineering & Theory Center
Bldg., Cornell University, Ithaca, NY 14853-3801

Cornell University is an Equal Opportunity Educator and Employer


From: E. B. Saff <>
Date: Wed, 2 Dec 92 14:40:18 EST
Subject: New Positions at University of South Florida


We invite applications for two tenure-track positions at the Assistant
Professor level effective August, 1993, contingent on availability
of funds. Applicants must have or expect to have a PhD in mathematics
upon assuming the position, and must show evidence of strong research
potential. Candidates demonstrating research experience beyond the PhD
are particularly encouraged to apply. The duties include research
activity and both graduate and undergraduate teaching. We encourage
applications from the following fields: Analysis, Discrete Mathematics/
Foundations of Computing, Numerical Analysis, Probability. Applicants
must indicate in which of these four fields they wish to be considered,
although outstanding candidates in other areas may apply.

The University of South Florida is the second largest state university
in the Southeast, with more than 34,000 students enrolled. The Mathematics
Department offers BA, MA, and PhD degrees.

To apply, send a letter of application and a curriculum vitae, and arrange
to have at least three letters of recommendation sent to: Kenneth L.
Pothoven, Chair, Department of Mathematics, University of South Florida,
4202 E. Fowler Ave., PHY 114, Tampa, FL 33620-5700 (e-mail:, fax: (813) 974-2700).

Applications, which may be submitted by e-mail or fax, must be
submitted by Feb. 1, 1993. U.S.F. is an Equal Opportunity/Affirmative
Action Employer, and follows ADA guidelines.


From: Anthony D Klemm <tony@deakin.OZ.AU>
Date: Mon, 30 Nov 92 10:54:14 +1100
Subject: Chaotic Numerics Conference

An International Workshop on the Approximation and
Computation of Complicated Dynamical Behaviour

12-16 JULY 1993

Much of what we know about specific dynamical systems is obtained from
numerical experiments. Not only can we visualise the dynamics, we can also
evaluate key characteristics such as bifurcation parameters, Lyapunov
exponents, Hausdorff dimension or entropy. The discretization procedure
usually has no significant effect on the results for relatively simple,
well-behaved dynamics. On the other hand, acute sensitivity to changes
in initial conditions is a hallmark of chaotic behaviour, so how confident
can we be that the numerical dynamics reflects that of the original system?
Do we always obtain a nearby attractor, homoclinic orbit or inertial manifold?
Do numerically calculated trajectories always shadow a true one? In brief,
what role does numerical analysis have in the study of dynamical systems?
Conversely, can recent advances in dynamical systems theory provide new
insights into our understanding of numerical algorithms?

The purpose of this workshop is to provide a forum for researchers and
practitioners to discuss these fascinating issues at the interface of
numerical analysis and dynamical systems theory, and their implications
in science and


W.J. Beyn University of Bielefeld
S.N. Chow Georgia Institute of Technology
J. Hale Georgia Institute of Technology
J. Lorenz University of New Mexico

Each keynote speaker and other invited speakers will present survey and
research lectures. Short talks or computing demonstrations from
conference participants are invited. A proceedings of selected papers will
be published by an international publisher and sent to participants after
the workshop, the cost being included in the registration fee.


P.Kloeden (Geelong) K. Palmer (Miami)
K. Burrage (Brisbane) A. Pokrovskii (Moscow)

For additional registration forms and information please contact one of the

Prof. P.E. Kloeden
School of Computing and Mathematics
Deakin University
Geelong Victoria 3217
Email: kloeden@cm.deakin

Prof. K.J. Palmer
Dept. of Mathematics and Computer Science
University of Miami
Coral Gables
Florida 33124 USA

Chaotic Numerics is sponsored by the Australian Mathematical Society and Deakin


From: Anthony D Klemm <tony@deakin.OZ.AU>
Date: Mon, 30 Nov 92 10:59:14 +1100
Subject: Computational Techniques Conference

JULY 5th-9th, 1993

About the Conference

CTAC93 is the sixth biennial conference on computational techniques and
applications organised by the Computational Mathematics special interest
group of the Applied Mathematics Division of the Australian Mathematical
Society. The conference, to be held on July 5, 6 and 7, provides an
opportunity for the developers and implementors of computational methods
to interact with those applying the technology to problems in engineering
and science, in particular. The workshops, to be held on July 8 and 9,
provide in-depth treatment of important recent developments in particular
areas of computational mathematics and computing technology.


The conference and workshops will be held in the Faculties area of the
Australian National University adjacent to the School of Mathematical
Sciences. Close by are the Student Union and the concessions area which
provide a range of commercial, eating, entertainment and sporting
facilities. The venue is only a few minutes walk from the city centre.

Invited Speakers

Anthony Cooper (Lausanne): Stability calculations in MHD and Plasmas.

Charles Elliott (Sussex): Numerical Analysis of the Phase Field
Equations and Phase Boundary Motion.

David Green (ANU): Numbers versus rules? Alternative paradigms in

Andreas Griewank (Argonne): Challenges in computational differentiation.

Steve McCormick (U.C. Denver): Multilevel projection methods.

Joe Monaghan (Monash): Particle methods.


The final two days of CTAC93 will be devoted to workshops consisting
of groups of related presentations in areas of specific interest.
The basic format for each presentation will consist of two lectures.
The first will have the character of an area survey and will be followed
by a second which will treat some aspect in greater depth.
The workshops that have been organised are:

`Computational problems in fluids, MHD, and plasmas.'
Organiser: Henry Gardner, Theoretical Physics, ANU.

`Optimization, complementarity problems, and variational
Organisers: David Stewart, School of Mathematical Sciences, ANU, and
Robert Womersley, School of Mathematics, UNSW.

`Programming distributed memory multiprocessors.'
Organisers: David Singleton, Supercomputer Facility, ANU, and
Lindsay Hood, TMC.

CTAC Lecture

Mr. Trevor Robinson, adviser to the Minister for Industry, Technology
and Commerce will give an individual view of supercomputer developments and
related policy and application questions in science and industry. This
keynote address will be held in Bruce Hall on Tuesday evening, July 6,
and will include dinner. Guests of participants are welcome to attend,
at a cost of $40.00 per guest. This fee for guests should be paid with
the registration fee.

Conference Information

An information file on the Conference, `', is held in the
ftp directory pub/CTAC93 on
and is available for access by anonymous ftp (log in as anonymous and use
your email address as password). This is a directory to files containing
preliminary information on the programs for the conference and workshops,
general information about the conference venue, instructions for preparing
abstracts and papers etc. General inquiries may be directed to


From: Andy Wathen <>
Date: Wed, 2 Dec 92 16:31:22 GMT
Subject: Bristol-Bath Numerical Analysis Day

The next


will be held in Lecture Theatre SM2, School of Mathematics,
University Walk, Bristol, UK on Wednesday 6th January 1993.

All are invited to attend this informal (and free!) set of
talks on current research to be given by local speakers:
Yves Tourigny, Ivan Graham, Alan Champneys,
Alison Ramage, Adrian Hill, Chris Budd
and our `guest' speaker, Dr Nick Higham of Manchester University.

The talks will start at 10:45 preceded by coffee (from 10:15),
and will end at 16:05.

For full programme contact:
Andy Wathen (+44 0272 303313)


From: Karen Hahn <>
Date: Wed, 2 Dec 92 15:12:49 EST
Subject: IMACS Conference on Expert Systems for Numerical Computing


May 17-19, 1993
Purdue University
West Lafayette, Indiana, USA

Conference Rationale:

Many diverse groups have started work on projects to aid in the use of
complex software systems, and to guide nonspecialists in the many
choices that have to be made when they want to use computers for
scientific applications. This international conference will bring
together active researchers to exchange ides, viewpoints, and

Topics of Interest (include, but are not limited to):

* Artificial intelligence and expert systems for numerical computing
(e.g. for numerical solution of ordinary or Partial differential equations,
integral equations, linear systems...)
* Knowledge-based systems for scientific application
* Expert systems for mapping applications to parallel architectures and to
support parallel processing
* Advisory expert systems for general-purpose scientific software libraries
* Tools and methods for knowledge acquisition about numerical computing
* Problem solving environments for scientific/engineering applications
* Natural language for scientific interfaces

Submission of Papers:

The conference will include invited and contributed papers. Authors should
submit three copies of an extended abstract (two or three typewritten pages)
by January 15, 1993. Contributors will be notified regarding acceptance by
February 28, 1993. Deadline for final manuscripts is June 1, 1993. Abstracts
and inquiries should be sent to the conference coordinator:

Dr. Elias Houstis
Purdue University
1398 Computer Science Building
West lafayette, IN 47907, USA
Tel: 317-494-6181
Fax: 317-494-0739

Organizing Committee: E. Houstis (Purdue); J. R. Rice (Purdue);
R. Vichnevetsky (Rutgers)

Program Committee: W. Enright (U. of Toronto); E. Gallopoulos (U. of Illinois)
I. Gladwell (Southern Methodist U.); E. Kant (Schlumberger
Lab); T.S. Papatheodorou (U. of Patras, Greece);
R. L. Peskin (Rutgers U.) F. Rechenmann (INRIA, France);
S. Steinberg (U. of New Mexico); Y. Umetani (Hitachi Ltd.,


From: Federico Malucelli <>
Date: Fri, 4 Dec 92 18:47:33 MET
Subject: Workshop on Network Optimization


October 3-7, 1993

Centro Studi "Cappuccini", Cassa di Risparmio di S. Miniato,
San Miniato (PI) Italy.

Sponsored by:
Mathematical Programming Society
Hewlett-Packard Italy Ltd.
IBM Italy Ltd.
Italian Operations Research Society
CNR - Progetto Finalizzato Trasporti
Universita' di Pisa

This workshop will emphasize recent theoretical and computational
advances in the field of network optimization, related continuous
and combinatorial optimization problems, implementations and
applications. Netflow93 will be organized in sequential sessions
of invited and contributed papers with sufficient time for
individual discussions among participants.

TOPICS: A variety of topics will be accommodated, such as single
and multicommodity network flows, matching, network design,
scheduling theory and algorithms, computational complexity, graph
partitioning algorithms, nonlinear network optimization,
combinatorial optimization, large-scale network optimization, fast
approximation algorithms, implementations and computational
experimentation, as well as significant applications.

EXTENDED ABSTRACTS and FULL PAPERS: Contributed papers will be
selected by the Program Committee on the basis of Extended
Abstracts. Extended abstracts for all talks will be made available
to participants during the Workshop. The Netflow93 Proceedings,
planned for 1994 as a Mathematical Programming-B journal volume,
will contain full papers which will be refereed according to the
established policies of the journal.

M.D. Grigoriadis, M. Grotschel, L.G. Khachiyan, F.T. Leighton,
J.K. Lenstra, T.L. Magnanti, J.B. Orlin, W.R. Pulleyblank,
B. Simeone, E. Tardos, R.E. Tarjan, P. Toint.

Netflow93 CO-CHAIRMEN: Giorgio Gallo and Mike Grigoriadis.

LOCATION: The workshop will be held in the Centro Studi "Cappuccini",
a recently restored medieval monastery on the hills of the historic
town of San Miniato, located midway between Pisa and Florence, an
area rich in cultural sites.

April 15, 1993: All Extended Abstracts received in Italy.
May 15, 1993: Notification to authors.
August 31, 1993: Revised Extended Abstracts received in Italy.
October 3, 1993: Arrival at San Miniato.
October 4-6, 1993: Netflow93 Workshop.
October 7, 1993: Departure.
December 31, 1993: Full papers received by either Co-Chairman
of Netflow93 for refereeing and possible
publication in Mathematical Programming-B.

INFORMATION and CORRESPONDENCE: Please send all inquiries,
applications for registration and Extended Abstracts to:

Federico Malucelli, Chairman
Local Organizing Committee - Netflow93
Dipartimento di Informatica
Universita di Pisa
Corso Italia 40, 56125 Pisa, Italy.
Phone: +39 -50 510216
Fax: +39 -50 510226


From: Ralph B Kearfott <
Date: Sat, 5 Dec 92 19:01:43 CST
Subject: Numerical Analysis with Automatic Result Verification


Conference on Numerical Analysis with Automatic Result Verification
Lafayette, Louisiana
February 25 through March 1, 1993.

A preliminary program, as the names, addresses, and email addresses of
speakers, and a description of the social events are now available.
These can be provided through regular mail or in Plain TeX and ASCII formats,
via FTP as follows:

1. FTP to

2. The information is in /pub/interval_math/conference as follows:

a) nametime.tex gives an alphabetical listing by first author,
with time of the talk.

b) schedule.tex gives a chronological list of author names and
titles, with session names as headings.

c) topics.tex gives a listing of the titles of the talks,
divided into subject areas, and with addresses and Email
addresses of authors.

d) authors.tex gives an alphabetical listing by first author, with
titles, addresses, and email addresses.

e) social.tex gives brief information about the social events, as
well as other important conference information.

f) overall.asc gives a "schedule at a glance" in ASCII format.
Warning: schedule.asc has records (lines) which are 106
characters long.

We will send the documents in printed form upon request.

The Lafayette Holidome has told me that the block of rooms will remain
available until February 4. Please make reservations accordingly.

The National Science Foundation has officially provided funds. These
funds are meant primarily to encourage graduate students and young
researchers within the United States, but without other funding, to
attend. We strongly encourage such persons to apply for support. It is
also still possible to schedule presentations.

To request support, send a statement of interests and a short vita.
State whether funds are needed immediately, or if reimbursement is
adequate. Include a social security number. We prefer to receive the
requests via Email, if possible. Send the information to:

or to:

R. Baker Kearfott
Interval Methods Conference
Department of Mathematics
University of Southwestern Louisiana
U.S.L. Box 4-1010
Lafayette, LA 70504-1010

Phone: (318) 231-5270
Home : (318) 981-9744 (Recommended from 12/18/92 to 01/04/93.)

Members of groups underrepresented in the mathematical sciences in the
United States are particularly encouraged.


From: neabbs!
Date: Fri Dec 4 10:49:24 1992
Subject: IMACS Annals of Computing and Applied Mathematics

IMACS Annals of Computing and Applied Mathematics

Volume 12: E. Kaucher, S.M. Markov and G. Mayer (Eds), Computer Arithmetic
Scientific Computation and Mathematical Modelling

Volumes 10 & 11: R. Hanus, P. Kool and S. Tzafestas (Eds), Mathematical and
Intelligent Models in System Simulation

Volume 9: C. Brezinski, L. Gori and A. Ronveaux (Eds), Orthogonal Polynomials
and their Applications

Volume 8: P. Borne and V. Matrosov (Eds), Lyapunov Functions, Methods and

Volume 7: C. Ullrich (Ed.), Contributions to Computer Arithmetic and
Self-validating Numerical Methods, SCAN '89

Volume 6: J. Robert and W. Midvidy (Eds), Electrical and Power Systems
Modelling and Simulation

Volume 5: J. Eisenfeld and D.L. Levine (Eds), Biomedical Modelling and

Volume 4: P. Borne, S.G. Tzafestas, P. Breedveld and G. Dauphin-Tanguy (Eds),
Computing and Computers for Control Systems

Volume 3: P. Breedveld, G. Dauphin-Tanguy, P. Borne and S.G. Tzafestas (Eds),
Modelling and Simulation of Systems

Volume 2: R. Huber, X. Kulikowski, J.M. David and J.P. Krivine (Eds),
Artificial Intelligence in Scientific Computation: Towards Second Generation

Volume 1, 2 parts: W.F. Ames and C. Brezinski (Eds), Numerical and
Applied Mathematics

Price per volume: Institutional price Sfr. 218.00/$ 156.00 / Personal
price per volume Sfr. 130.00 / $ 92.00. Prices include distribution costs.
Extensive brochure available upon request.
Please send your order to: J.C. Baltzer AG, Science Publishers, Wettsteinplatz
10, CH-4058 Basel, Switzerland, Fax: +41-61-692 42 62, E-mail:


End of NA Digest