[ut.na] NA Digest Volume 88 : Issue 23

krj@csri.toronto.edu (Ken Jackson) (06/13/88)

NA Digest   Monday, June 13, 1988   Volume 88 : Issue 23

Today's Editor: Cleve Moler

Today's Topics:
 
     Conference on Iterative Methods for Large Linear Systems
     First SIAG/LA Linear Algebra Prize
     Source for DEROOT and ODERT
     Winnipeg Numerical Analysis Meeting
     NATO Institute on Orthogonal Polynomials
     Contributions to Floating-Point Indoctrination
     AMS Reviews in Partial Differential Equations
     Two Tenured Positions at University of Umea
     Minnesota IMA Summer Program on Signal Processing
     Conference on Applications of the Connection Machine
     Rational Approximation of Floating Point Numbers

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

From: Bob Ward <ward@msr.epm.ornl.gov>
Date: Mon, 6 Jun 88 16:52:21 EDT
Subject: Conference on Iterative Methods for Large Linear Systems

              Second Announcement and Registration Form
        CONFERENCE ON ITERATIVE METHODS FOR LARGE LINEAR SYSTEMS
                      October 19, 20 and 21, 1988
          Celebrating the 65th birthday of David M. Young, Jr.    

OBJECTIVE:  This conference will be dedicated to providing an overview of the
state of the art in the use of iterative methods for solving sparse linear
systems with an eye to contributions of the past, present, and future.  The
emphasis will be placed upon identifying current and future research 
directions in the mainstream of modern scientific computing.  Recently, the
use of iterative methods for solving linear systems has experienced a 
resurgence of activity as scientists attack extremely complicated three
dimensional problems using vector and parallel supercomputers.  Many 
research advances in the development of iterative methods for high-speed
computers over the past forty years will be reviewed as well as focusing on
current research.

INVITED SPEAKERS:
L. Adams (Washington University)
O. Axelsson (University of Nijmegen, Netherlands)
G. Birkhoff (Harvard University)
P. Concus (Lawrence Berkeley Laboratory)
L. Ehrlich (John Hopkins University)
H. Elman (University of Maryland)
G. Golub (Stanford University)
L. Hageman (Bettis Atomic Power Laboratory)
R. Lynch (Purdue University)
T. Manteuffel (Los Alamos National Laboratory)
J. Ortega (University of Virginia)
J. Rice (Purdue University)
P. Saylor (University of Illinois)
R. Varga (Kent State University)
W. Wachspress (University of Tennessee)
M. Wheeler (Rice University)
O. Widlund (Courant Institute)
D. Young (University of Texas)   

ORGANIZATION:  The host organization is the Center for Numerical Analysis
(CNA) of The University of Texas at Austin.  The members of the local
organizing committee are D. Kincaid, L. Hayes, G. Carey and W. Cheney.  The
conference is being co-sponsored by the Special Interest Groups for Linear
Algebra and Supercomputing of the Society for Industrial and Applied
Mathematics.

ACCOMMODATIONS:  To make reservations call the Austin Marriott at the Capital
[(512) 478-1111 or (800) 228-9290] or mail the enclosed card for rooms at the 
special conference rate of $55 for single or double rooms.  All reservations 
are handled on a first-come-first-served basis.  Reservations must be received 
by October 4, 1988.  Reservations made after this date are subject to room 
availability.  

REGISTRATION:  Conference advanced registration is $95 (SIAG/LA or SIAG/SC
member $85), if received by September 1, 1988.  If paid after this date or
at the conference, the registration fee is $125.  This fee includes morning 
and afternoon coffee breaks, a reception, a banquet honoring Professor Young,
and other activities.  The student registration fee is $15 which allows 
admission to the technical sessions and coffee breaks only.  To register, 
detach and mail the registration form below.  For additional information, 
contact the CNA at the address below or at Tel: (512) 471-1242; 
Arpanet: sheri@sally.utexas.edu; Bitnet: sheri@uta3081.

                     Mrs. Katy Burrell
                     Conference Secretary
                     Center for Numerical Analysis
                     RLM Bldg 13.150
                     University of Texas at Austin
                     Austin, Texas 78713-8510

     .........................Detach and mail.............................

Name:
Organization:
Address:


Telephone:
Email:
Number of guest banquet tickets ($27.50 per person):
Amount Enclosed:
                (Make checks payable to The University of Texas at Austin)

___ Yes, I plan to attend.  Enclosed please find my registration fee of $_____ 

___ I am not ready to register yet, but send me additional information as it
    becomes available.


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

From: Bob Ward <ward@msr.epm.ornl.gov>
Date: Wed, 8 Jun 88 10:13:39 EDT
Subject: First SIAG/LA Linear Algebra Prize

                    PRESENTATION OF THE FIRST
                  SIAG/LA LINEAR ALGEBRA PRIZE

   The first SIAG/LA Linear Algebra Prize  was  presented  to  James
   Demmel for his paper "On Condition Numers and the Distance to the
   Nearest Ill-Posed Problem," Numer. Math 51 (1987) 251-289.    The
   Prize  Plaque  and  Citation  were presented to Demmel by SIAG/LA
   Chair Bob Ward  and Vice-Chair David Carlson  at  the Third  SIAM  
   Conference on Applied Linear Algebra  held in  Madison, Wisconsin  
   May 23-26, 1988.   After  the  ceremony,  Demmel gave  a stirring  
   half-hour  account of his work in the area of the prize paper.

   The winning paper was selected by a Prize Committee consisting of
   Dave Carlson (chair), Ake Bjorck, Gene Golub, Roger Horn, and Tom
   Kailath.  Altogether there  were  23  1986  and  1987  papers  in
   applicable  linear  algebra  nominated.  Preliminary judging by 3
   subcommittees narrowed the field to 6 finalist papers.   Demmel's
   paper, together with

   T. Ando, Roger Horn, and Charles Johnson, The singular values  of
   a  Hadamard  product:   a  basic  inequality, Lin. Multilin. Alg.
   21(1987) 345-366.

   Thomas Coleman  and  Alex  Pothen,  The  null  space  problem  I.
   Complexity, SIAM J. Alg. Disc. Meth. 7 (1986) 527-537.

   Pamela  Coxson,  Loren  Larson,  and  Hans  Schneider,   Monomial
   patterns  in  the  sequence  A sup k b, Lin. Alg. Appl. 94 (1987)
   89-101.

   Chris   Paige,   Computing   the   generalized   singular   value
   decomposition.  SIAM J. Sci. Stat. Comput. 7 (1986) 1126-1146.

   Ion Zaballa, Matrices with prescribed rows and invariant factors,
   Lin. Alg. Appl. 87 (1987) 113-146

   (Horn did not take part in the  final  judging.)   Future  Linear
   Algebra Prizes will be awarded every two years by the SIAG/LA.


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

From: Edmond Ng <esmond@msr.EPM.ORNL.GOV>
Date: Fri Jun  3 12:48:34 1988
Subject: Source for DEROOT and ODERT

Several people at the Oak Ridge National Laboratory are looking for
DEROOT and ODERT which are ode solvers written by Shampine and
Gordon.  If anyone knows where and how I can get a copy of the
routines, please let me know.

Esmond Ng (esmond@msr.epm.ornl.gov)
Mathematical Sciences Section
Oak Ridge National Laboratory
P.O. Box 2009, Bldg. 9207-A
Oak Ridge, TN 37831-8083


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

From: Peter Aitchison <AITCHIS%Uofmcc.Bitnet@Forsythe.Stanford.EDU>
Date: Fri, 03 Jun 88 14:10 CDT
Subject: Winnipeg Numerical Analysis Meeting

          CAMS/SCMA TENTH ANNUAL MEETING
AND SYMPOSIUM ON ASYMPTOTIC & COMPUTATIONAL ANALYSIS
-
THE TENTH ANNUAL MEETING OF THE CANADIAN APPLIED MATHEMATICS SOCIETY
WILL BE HELD AT THE UNIVERSITY OF MANITOBA, WINNIPEG, CANADA ON
JUNE 7, 8 AND 9,  1989 (NEXT YEAR).
THE MAJOR THEMES AND PRINCIPAL SPEAKERS OF THE MEETING INCLUDE:
   1. MATRIX COMPUATION
 A.J. GEORGE
 G. GOLUB
 W.G. STRANG
  2. TWO-POINT BOUNDARY VALUE PROBLEMS
 F.V. ATKINSON
 H.B. KELLER
  3. APPLICATIONS OF SPECIAL FUNCTIONS TO STATISTICS
 C.R. RAO (PITTSBURGH)
-
PAPERS ARE NOW BEING SOLICITED FOR PRESENTATION ON THE ABOVE ASPECTS
OF APPLIED MATHEMATICS.
   THE CAMS/SCMA MEETING WILL OVERLAP WITH AN INTERNATIONAL SYMPOSIUM
ON ASYMPTOTIC AND COMPUTATIONAL ANALYSIS WHICH WILL BE HELD ON JUNE
5, 6 AND 7, 1989.  FOR FURTHER DETAILS AND PAPER SUBMISSION TO EITHER
THE MEETING OR THE SYMPOSIUM CONTACT:
  PROFESSOR RODERICK WONG
 DEPARTMENT OF APPLIED MATHEMATICS
 UNIVERSITY OF MANITOBA
 WINNIPEG, MANITOBA, CANADA C3T 3A6
 PHONE (204) 474-8167
 E-MAIL: AITCH@UOFMCC.BITNET
OR      AITCH@SCORE.STANDFORD.EDU
 SIGNED  P.W. AITCHISON  (ORGANIZER OF THE MATRIX COMPUATION SESSION)


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

From: Paul Nevai <pgn@osupyr.mast.ohio-state.edu>
Date: Sat, 4 Jun 88 07:36:50 EDT
Subject: NATO Institute on Orthogonal Polynomials


	NATO Advanced Study Institute (Paul Nevai, Director) on  
	
	      "Orthogonal Polynomials and Their Applications"
	
	The Ohio State University, Columbus, Ohio 43210, U. S. A.
		
			May 22, 1989 - June 3, 1989.


Main Subjects: Orthogonal Polynomials and Their Applications in
	Approximation Theory, Coding Theory,Combinatorics, Communication
	Engineering, Continued Fractions, Difference Equations, Julia Sets,
	Nuclear Physics, Numerical Analysis, Pade Approximations, Potential
	Theory, Prediction Theory, Rational Approximation, Recursions, 
	Representation Theory, Scattering Theory, Signal Processing, Solid
	State Physics and  Special Functions. 

Organizing Committee: M. Ismail, P. Nevai (Director) and D. Stanton

Principal Speakers: D. Bessis, W. Gautschi, Y. Genin, R. Haydock,
	T. Koornwinder, D. S. Lubinsky, I. Macdonald,  E. A. Rahmanov,
	E. B. Saff, H. Stahl, and G. Viennot

Attendance is strictly by application/invitation only, and it is limited to
	approximately one hundred participants.

Partial financial support available for graduate students and scientists
	from NATO nations (and possibly from other countries as well) 
	on a "first come first serve" basis. 

Information:
	OPsConf
	c/o Paul Nevai
	Department of Mathematics
	The Ohio State University
	231 West Eighteenth Avenue
	Columbus, Ohio 43210-1174
	United States of America
 
Email: 	ts1171@ohstvma.bitnet
	pgn@osupyr.mast.ohio-state.edu

Phone: 	1-(614)-292-4975
	1-(614)-292-5310


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

From: David Hough <dgh@Sun.COM>
Date: Fri, 3 Jun 88 21:46:57 PDT
Subject: Contributions to Floating-Point Indoctrination

The Floating-Point Indoctrination Lectures, being presented by
W. Kahan at Sun Microsystems in Mountain View, are nearing the halfway 
point with about 58 paying attendees, 21 absentees, and some full-time students.   
Of the total 32 are Sun employees and the remainder are from a variety of other 
organizations.  The backgrounds and objectives of the participants are
sufficiently varied to defy generalization.

The purpose of this note is to solicit donations of technical 
information about commercial products associated with na-net readers.
If your product falls within the realm of floating-point hardware
or mathematical software and you are willing to donate 100 copies
of literature describing it then please mail the material to

	David Hough
	MS 12-40
	Sun Microsystems
	2550 Garcia Av
	Mountain View, CA 94043

It would be prudent to mail by early July to insure reaching me before the
last class session.  What is most useful from the participants' point
of view is technical material like user's reference manuals.

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

From: William LeVeque <LEV@MATH.AMS.COM>
Date: Tue 7 Jun 88 10:42:09-EDT
Subject: AMS Reviews in Partial Differential Equations

ANNOUNCING 
A New Publication from the
American Mathematical Society

REVIEWS IN PARTIAL DIFFERENTIAL EQUATIONS, 1980-86
Introduction by Murray H. Protter

Comprising a significant portion of present-day research in analysis,
the area of partial differential equations encompasses a broad spectrum 
of topics, from classical work in linear second-order equations to more
recent work in a general nonlinear setting.  In addition, the subject
has deep and fundamental ties to a wide variety of scientific areas 
outside mathematics.  This important reference work makes the vast 
subject of partial differential equations much more accessible both to
specialists working in this area and to those interested in related areas
of mathematics and its applications.

The five volumes of REVIEWS IN PARTIAL DIFFERENTIAL EQUATIONS, 1980-86,
contain the more than 19,200 reviews that appeared in Mathematical
Reviews from 1980 through 1986 and have a primary or a secondary
classification in Partial Differential Equations (classification number 35).
Relevant cross-references are provided with each review.  The fifth volume
of this set contains author and key indexes which make it very easy to locate
items written by a specific author or to get information about collections
or conference proceedings dealing with partial differential equations.

It is expected that this work will be followed by sequels, in the future.

4,040 pages in 5 volumes, Softcover, June 1988 
ISBN 0-8218-0103-1, LC 88-6681
List $295, AMS Institutional Member $236, AMS Individual Member $177,
Reviewer $148
To order, please specify REVPDE/86NET

PREPAYMENT IS REQUIRED.   Send orders with remittance to the American
Mathematical Society, Annex Station, P. O. Box 1571, Providence, RI 
02901-9930 USA or order by phone in the continental U.S. and charge your 
books to VISA or MasterCard -- call 800-556-7774.


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

From: Axel Ruhe <ruhe%cs.chalmers.se@relay.cs.net>
Date: 8 Jun 88 14:31 +0200
Subject: Two Tenured Positions at University of Umea

Announcing  two tenured chairs as professor in

1. NUMERICAL ANALYSIS with special emphasis on
   parallel computations

2. DISCRETE MATHEMATICS with computing applications

at the University of Umea Sweden.

Umea is far enough north to need no street lights this part
of the year. It is small enough to be traversed by bicycle 
but large enough to have an Opera House.
The university started as a medical school in 1959,
and is strongest in the biomedical area, but is now also
expanding strongly into the computation field with a o
an educational program for specialists in Scientific Computation.
Skelleftea just to the north has a supercomputer center and
a parallel machine for experimentation is under delivery to Umea.

Applications will be screened by 3 experts, before
decision by the university.

Deadline for application is June 27, 1988. A written application
must have reached the University of Umea at that time.

Postal address: Universitetet, S-90187 Umea, Sweden

Telex:  54005 UNIVUME S

Telefax: int-46-90165488

The application should be supported by a c.v., list of publications,
copies of relevant publications and a short description of the
applicants research achievments and future plans. This supporting
material may arrive 3 weeks after the application date, and should
be sent in 4 copies.

Information can be obtained from 
Bo Kagstrom, Telephone int-46-90165419, email bokg@seumdc51.bitnet
Per Ake Wedin, Tel int-46-90165439

and of course from myself who  worked there the best part of
my carreer 1970-83,

   Axel Ruhe
email: ruhe@cs.chalmers.se
Telephone  int-46-31721096 (office)
	   int-46-31483168 (home)


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

From: Willard Miller <miller@csfsa.cs.umn.edu>
Date: Wed, 8 Jun 88 11:31:20 cdt
Subject: Minnesota IMA Summer Program on Signal Processing

         INSTITUTE FOR MATHEMATICS AND ITS APPLICATIONS

                  University of Minnesota
                    514 Vincent Hall
                  206 Church Street S.E.
               Minneapolis, Minnesota 55455
        (612)624-6066   ima_staff%csfsa@umn-cs.cs.umn.edu

                     Summer Program on 
                     SIGNAL PROCESSING 
                  June 27-August 5, 1988  

        Organizers: T. Kailath (Chairman), L. Auslander 
        A. Grunbaum, W. Helton, P. Khargonekar, S. Mitter
 
The basic objective of the IMA program is to interest a broad set of 
mathematicians in research into the challenging problems posed by 
Signal Processing and by bringing mathematicians and other experts 
in the field together for an extended period, to make significant 
research progress toward the solution of these problems.

The program will be an integrated approach to one-dimensional and 
multidimensional problems in Signal Processing.  Thus the first two
 weeks will be devoted to a broad range of problems and methods.  
An effort will be made to promote new interaction also within
 one-dimensional research groups (such as the linear control and 
the nonlinear control people) and within the multi-dimensional
groups (such as radar, sonar and medical imaging).

The first two weeks will be concerned with broad general issues.
The next four weeks will be somewhat less structured and will include
periods of concentration in both 1-dimensional and multidimensional 
topics.

                       OUTLINE
June 27-July 10 (Weeks 1 and 2)
Expository lectures on Problem Areas & Methods

July 11-24 (Weeks 3 and 4}
Period of concentration:  Digital filter & VLSI implementation. 
                          Integrable circuit modelling

July 25-31 (Week 5)
Period of concentration:  Robust & nonlinear control with aerospace 
                          applications

August 1-5 (Week 6)
Period of concentration:  Problems in radar, sonar & medical imaging


During July 11-15 (week 3) there will be a special session on ``Signal
Processing''at the 1988 annual meeting of the Society for Industrial 
and Applied Mathematics  (SIAM).  The annual meeting is being
held in downtown Minneapolis. The special session will consist of:

     (1) One hour expository lecture by Gerard Bricogne (Mathematical
         Crystallography), Paris/Sud and CNRS

     (2) Two half day mini-symposia organized by:

         (i)  Donald E. McClure, Brown University  
        (ii)  Mostafa Kaveh, University of Minnesota

      
                     PROGRAM FOR WEEK 1
         Expository lectures on problem areas and methods 

                     Monday, June 27

9:00 am     Sanjoy Mitter            MIT 
Variational and Probabilistic Problems in Image Analysis, Part I

10:30 am   William Helton         UC, San Diego 
Worst Case Design in the Frequency Domain

2:30 pm   Tom Kailath            Stanford University 
A Displacement Structure of Matrices and its Applications

               Tuesday, June 28

9:00 am    Marvin Bernfeld        Raytheon Co. 
Signal Processing Concepts in Radar

10:30 am    Alberto Grunbaum          UC, Berkeley 
Solitons in Signal Processing

2:30 pm    Thomas S. Huang            U. of Illinois-Urbana  
Linear Algorithms for 3-D Motion Estimation from Image Sequences

             Wednesday, June 29

9:00 am    Sanjoy Mitter             MIT 
Variational and Probabilistic Problems in Image Analysis, Part II
 
10:30 am    Israel Gohberg           Tel Aviv University 
Interpolation Problems for Matrix Functions

2:30 pm    Richard Roy                Stanford University 
Large Geometric Methods and Invariance Techniques in Multidimensional
Signal Processing

              Thursday, June 30

9:00 am    Jonathan Allen               MIT 
Computer Architecture and VLSI Implementation for Digital Signal 
Processing, I

10:30 am    Louis Auslander            CUNY 
Nonstationary Processes

2:30 pm    Jonathan Allen                 MIT 
Computer Architecture and VLSI Implementation for Digital Signal Processing, II

                 Friday, July 1

9:00 am    Pramod Khargonekar             University of Minnesota
Robust Stability and Stabilization

10:30 am    Allen Tannenbaum              University of Minnesota 
Generalized Interpolation in the Robust Control of Uncertain Systems


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

From: Horst Simon <simon@orville.nas.nasa.gov>
Date: Wed, 8 Jun 88 14:03:17 PDT
Subject: Conference on Applications of the Connection Machine

        Scientific Applications of the Connection Machine
           Conference Announcement and Call for Papers     

        NASA Ames Research Center, Moffett Field, CA 94035
                      September 12-14, 1988

                          Organized by
             Numerical Aerodynamics Systems Division, 
                    NASA Ames Research Center 

                        With Support from
                 Thinking Machines Corporation

                        PROGRAM COMMITTEE

                Bruce Blaylock  -- NASA Ames Research Center
                Creon Levit     -- NASA Ames Research Center
                Jill Mesirov    -- Thinking Machines Corporation
                Oliver McBryan  -- University of Colorado, Boulder
                Horst Simon     -- NASA Ames Research Center

 
                      ORGANIZING COMMITTEE

                Carol Bee-Latty -- Thinking Machines Corporation
                Lyz Dunham      -- NASA Ames Research Center
                Judy McWilliams -- NASA Ames Research Center


Objective:

NASA's Numerical Aerodynamic Simulation (NAS) Program, located at NASA
Ames Research Center near Mountain View, California, will be sponsoring
a conference on Scientific Applications of the Connection Machine from
September 12 to September 14, 1988. Focus of this conference will be the
application of the Connection Machine to the solution of large scale
computational problems in physics, in particular computational fluid
dynamics, chemistry, and engineering.


Program:

On the first day of the conference (Monday, 9/12/88), Thinking Machines 
will present an all-day tutorial on using the Connection machine.
The purpose of the tutorial is to familiarize the audience with the 
architecture and programming environment of the Connection Machine, and to
introduce data parallel programming as a methodology for utilizing a 
massively parallel SIMD machine. One of the presenters of the tutorial
will be Guy Steele, Jr. from Thinking Machines Corporation.

For experienced users of the Connection Machine there will be a workshop
on CFD application organized by Creon Levit.  For details on the workshop
contact Creon Levit directly.

The actual conference will be held on Tuesday and Wednesday, September 13-14.
The following researchers have been invited to give presentations
about their research using the Connection Machine:
	Alan Egolf       -- United Technologies
	Oliver McBryan   -- University of Colorado, Boulder
	James Sethian    -- University of California, Berkeley
	Creon Levit      -- NASA Ames Research Center
	Gary Demos       -- Whitney and Demos
	David Rogers     -- RIACS


CONTRIBUTED PAPERS:
Contributed presentations will be selected from the submitted abstracts.
If you are interested in presenting a 15 minute paper at the conference please 
submit a 200 word abstract by July 15, 1988 to Lyz Dunham, NASA Ames
Research Center, Moffett Field, CA 94035; or by e-mail to
dunham@prandtl.nas.nasa.gov. Selected speakers will be notified by July 29,1988.

PROCEEDINGS:
Proceedings of the conference will be published. Each speaker will be asked 
to provide a camera-ready copy of his paper by October 1, 1988.


                        GENERAL INFORMATION

LOCATION
 
  All technical sessions will be held at the NASA Ames Research Center,
  Moffett Field, CA 94035.  

TRANSPORTATION

  40 minutes from San Francisco International Airport
  20 minutes from San Jose International Airport
	Direct or connecting flights to every major city in the
	United States.

CLIMATE

  Bay Area temperatures in the fall range from warm days (75 degrees F) 
  to cool nights (47 degrees F), with the average daytime temperature
  about 62 degrees F.

HOTELS

  The following Hotels are conveniently located within NASA Ames Research
  Center area. Arrangements should be made directly with the Hotel of 
  your choice.

	The County Inn	(415) 961-1131
	850 Leong Drive, Mountain View, CA
	Rates*:  Government - $57.00  Corporate - $65.00/$67.00

	Sundowner Inn	(408) 734-9900
	504 Ross Drive, Sunnyvale, CA  94089
	Rates*:  Government - $57.00	Corporate - $72.00

	Comfort Inn	800-228-5150
	1561 El Camino Real West, Mountain View, CA  94040
	Rates*:  Government/Corporate - $55.00

	Best Western Sunnyvale Inn	800-528-1234
	940 Weddell Drive, Sunnyvale, CA  94089
	Rates*: Government - $54.00  Corporate - $51.00  Regular - $56.00

* All rates based on room availability

REGISTRATION FEES
  The regular registration fee is $75. This fee includes the tutorial and 
  conference, lunch on Tuesday and Wednesday, a dinner on Tuesday
  evening, and refreshments during the breaks. 


                        ADVANCE REGISTRATION

  Please use this form or a facsimile to pre-register.  Advance
  registration closes August 15, 1988.  Early registration is encouraged,
  since available space is limited. Participants will be registered on
  a first come basis.  Late registration is based on a space available
  basis and subject to a $25 late fee.

  Please mail your completed form with check or international money order 
  (US funds) payable to "Connection Machine Conference" to:

                     Connection Machine Conference
                       NASA Ames Research Center
                        c/o Ms. Lyz Dunham
                          Mail Stop 258-6
                      Moffett Field, CA 94035

  Requests for refunds will be honored until September 1, 1988.

  For further information, please call (415) 694-4370, or send
  electronic mail to:  dunham@prandtl.nas.nasa.gov


                          Registration Form

        Scientific Applications of the Connection Machine

  Name (last name first) ________________________________

  Affiliation ___________________________________________

  Address _______________________________________________

  _______________________________________________________

  City _______________________ State ____________________

  Zip/Postal Code ____________ Country __________________

  Phone number __________________________________________

  Electronic mail address (if applicable) _______________



  I will attend      _____    conference and tutorial

                     _____    tutorial only

                     _____    conference only

  Total enclosed:

                    $ ______  U.S.


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

From: Dimpy Pathria <clyde!watmath!watdragon!violet!dpathria@bellcore.com>
Date: 7 Jun 88 16:54:16 GMT
Subject: Rational Approximation of Floating Point Numbers

Does anyone know of numerical algorithms which, when given a number
x in [0..1), return the rational number (numerator/denominator)
that approximates x to within machine tolerance?

I know of a few methods for solving this problem (continued fractions, etc),
am interested in trying some different algorithms.  Thanks.
	
						Dimpy Pathria.

						dpathria@violet.waterloo.edu

[Editors Note: Of course, every floating point number is already rational,
and so is its own best rational approximation.  We must add the requirement
that the numberator and denominator be "small" integers.]


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

End of NA Digest
**************************
-------

Reposted by


-- 
Kenneth R. Jackson,                   krj@csri.toronto.edu (csnet)
Department of Computer Science,       uunet!csri.toronto.edu!krj (uucp)
University of Toronto,                krj@csri.toronto.cdn (ean x.400)
Toronto, Canada  M5S 1A4              krj%csri.toronto.edu@relay.cs.net (arpa)
(416) 978-7075                        krj@csri.utoronto (bitnet)