HDTenEightyP/NetNews huggingface dataset:
From: eijkhout@cupid.cs.utk.edu (Victor Eijkhout)
Newsgroups: sci.math.num-analysis
Subject: Re: LAPACK machine constants
Date: 27 Jan 93 14:57:29
Organization: /pearl/homes/eijkhout/.organization
Distribution: inet
NNTP-Posting-Host: cupid.cs.utk.edu
In-reply-to: kbriggs@mundoe.maths.mu.OZ.AU's message of Wed, 27 Jan 1993 06:31:02 GMT

In article <9302717.22929@mulga.cs.mu.OZ.AU> kbriggs@mundoe.maths.mu.OZ.AU (Keith Briggs rba8 7088) writes:

   The weird (and unusable) results are caused by the IBM representation of
   quadruple as two doubles.    In other words, DLAMCH has not been written
   in a sufficiently portable way.

   DOES ANYBODY KNOW THE CORRECT VALUES?

I'm sure that that information is IBM proprietary :-)

(The source of dlamch refers to a few papers with algorithms.
You might try to find out what assumptions about the architecture
they use that are not applicable to the RS/6000)



--
Victor Eijkhout ................................ `There are also a few bugs,
Department of Computer Science .......... though not as many as I've come to
University of Tennessee ............... expect in new [MS]Windows products.'
Knoxville TN 37919 ................................ (from a software review)
Newsgroups: sci.math.num-analysis
From: banana@panix.com (Walter Polkosnik)
Subject: Re: non-linear least-squares fitting
Organization: PANIX Public Access Unix, NYC
Date: Thu, 21 Jan 1993 08:26:07 GMT

In <1jkb5nINN8qn@iskut.ucs.ubc.ca> holland@geop.ubc.ca (Stephen Holland) writes:


>Does anyone out there know where I might find a good public domain routine 
>for doing non-linear least-squares fitting WITHOUT derivative information.
>I'm looking for something along the lines of POWELL in Numerical Recipes or
>CHIFIT in Bevington.  ForTran source would be nice since my software is 
>writen in ForTran but i can translate from C if need be.

>thanks

>steve holland

I have used subroutine LMDIF from MINPACK (which you can get from netlib) and
NL2SOL (which you can also get from netlib, as part of TOMS) extensively and
for all my applications they work great. You can always do some kind of
difference approximation to the derivatives if you don't want to calculate them
explicitly (which is what those two subroutines do).

Those two routines are also very simple to program around also.

-- 
Walter Polkosnik                 
Physics Department         banana@panix.com        
Queens College, CUNY       {cmcl2,apple}!panix!banana
Newsgroups: sci.math.num-analysis
From: mwette@csi.jpl.nasa.gov (Matt Wette)
Subject: test
Originator: mwette@mr-ed
Organization: Jet Propulsion Laboratory
Distribution: jpl
Date: Mon, 25 Jan 1993 18:39:49 GMT


test


-- 
mwette@csi.jpl.nasa.gov
From: jh0e@ns1.cc.lehigh.edu (JI-WEI HO)
Newsgroups: sci.math.num-analysis
Subject: How to get the manuel for GNUPLOT in public domain?
Date: 26 Jan 93 02:39:17 GMT
Organization: Lehigh University

Hi, I need a copy of user's manuel about GNUPLOT. If anyone knows where
I can get the manuel from public domain, please let me know. Many thanks in
advance.

Ji-Wei Ho
Department of Mechanical engineering and Mechanics
Lehigh University
Bethlehem, Pennsylvania 18015
U.S.A.
-- 
Newsgroups: sci.math.num-analysis
From: haase@zaphod.uchicago.edu (Mark Haase)
Subject: Elastic/Compression Wave Model
Keywords: PDE models, numerical methods, FEM
Organization: Dept. of Mathematics, U. of Chicago
Distribution: usa
Date: Thu, 21 Jan 1993 02:55:16 GMT

Dear Users:

I am a graduate student in applied mathematics at the University of 
Chicago and am working on finite element methods.  I am interested in
examining the propagation of acoustic waves (ultrasound) through the
human body using numerical methods assuming CT/MRI scans of the 
geometry and density.  Does anyone know of code or a mathematical
model of such a system (second order hyperbolic PDE's with parabolic-
energy loss)?  I am interested in attempting such a model but do not wish
to "re-invent" the wheel.  Any information that you might provide
would be *greatly* appreciated.  Thank you for your time.

Sincerely,

Chris Haase
DoD Fellow
University of Chicago

Newsgroups: sci.math.num-analysis
From: naylor@research.canon.oz.au (William Naylor)
Subject: simulated annealing question
Organization: Canon Information Systems Research Australia
Date: Wed, 27 Jan 1993 00:55:59 GMT

I am trying to minimize a real-valued function of about 50-500 real-valued
variables.  My function seems to have an exponential number of local minima,
so I have been trying to adapt SIMULATED ANNEALING to work on functions of
continuous variables.  Classically, simulated annealing [1] is designed to
work on discrete functions, with discrete domains.

Has anybody out there successfully used simulated annealing 
on continuous functions with continuous domains?  I would appreciate 
any advice, especially with references.  

Please respond by e-mail, I'll post a summary.


REFERENCES

[1]  Kirkpatrick S., Gelatt C. D., and Vecchi M. P.: "Optimization by
     Simulated Annealing", Science 1983, #220, pages 671-680.



-- 
Will Naylor               net:  naylor@research.canon.oz.au
                          mail: Canon Information Systems Research Australia  
phone: (61-2) 805-2921          P.O. Box 313 North Ryde, NSW 2113 
fax:   (61-2) 805-2929          Australia
From: sshankar@td2cad.intel.com (Sadasivan Shankar)
Newsgroups: sci.math.num-analysis
Subject: Re: infinity?
Date: 22 Jan 93 17:25:18 GMT
Reply-To: sshankar@td2cad.intel.com (Sadasivan Shankar)
Distribution: usa
Organization: Intel Corporation, Santa Clara, CA USA

Dividing by zero is not defined.  It is not pssible to compare dividing by a real number and
divind by zero.  If you look at the definition of functional spaces, for instance, multiplying
by zero itself is defined  as a separate operation.  Although tan (90) may not be defined
in this sense, cotangen (90) = 0.  Tangent-type functions (including) Cotangent are functions
with infinite discontinuties.  One way to see why tan (90) can't really be said to be
infinity is can be seen from the following example.

	Tan (0) = 0
	Tan (pi/4) = 1.
	Tan (90)_ = ?
	Tan  (90 + theta) = - cotangent (theta)

Thus to the right of pi/2 (in the period 0 - 2*pi), the tangent function starts from - (negative) Large
values.  Thus at pi/2, it is not exactly defined, since it could be +inf (approaching it from
left) or -inf (approaching it from right). Hope that this answers some of your questions.
	
S.Shankar
Tech CAD
INTEL


	
Newsgroups: sci.math.num-analysis,comp.lang.c++
From: robertd@kauri.vuw.ac.nz (Robert Davies)
Subject: newmat07: a matrix package in C++
Organization: Victoria University of Wellington
Date: Sun, 24 Jan 1993 09:33:10 GMT

Newmat07

I have released a new version of my matrix package in C++. This version
is called newmat07. This is largely a "maintenance" upgrade from
newmat06. You should upgrade.

There are some comments on its use with Gnu g++ at the end of this note.

The package supports classes Matrix, UpperTriangularMatrix,
LowerTriangularMatrix, DiagonalMatrix, SymmetricMatrix, BandMatrix,
UpperBandMatrix, LowerBandMatrix, SymmetricBandMatrix, RowVector,
ColumnVector.

Only one element type (float or double) is supported.

The package includes the operations *, +, -, inverse, transpose,
conversion between types, submatrix, determinant, Cholesky
decomposition, Householder triangularisation, singular value
decomposition, symmetric eigenvalue analysis, fast Fourier transform,
sort, print, an interface to "Numerical Recipes in C" programs, and an
emulation of exceptions.

It is suitable for matrices in the size range 15 by 15 up to the maximum
size that can conveniently be stored in a single block of memory. It can
be used with smaller matrices, but becomes less efficient.

The package works with AT&T C++ (versions 2.1 and 3), Gnu G++ (version
2.2), Borland C++ (version 3.1), Microsoft C++ (7.0), and mostly with
Zortech (version 3.04).

It is available on Simtel20 (192.88.110.20) in the pd1:<msdos.cplusplus>
directory in .zip format, and on the archives of comp.sources.misc,
volume 34 issues 107 to 114 (shar format). Look for it on
wuarchive.wustl.edu (128.252.135.4). It is also on Compuserve in the
Borland forum.


The package works under Gnu G++, version 2.2.2. There are a couple of
problems under the 2.3.x series.

There is an inline function Rectangular defined as part of class
MatrixType in file newmat.h. Gnu 2.3.x is unable to compile this inline.
This leads to an erroneous compilation in 2.3.1 and 2.3.2 and lots of
warning messages in 2.3.3. The solution is to move the body of the
function to one of the cxx files.

The ReturnMatrix code does not work with versions 2.3.1 and 2.3.2. As a
result Cholesky also does not work. There is a work-around, but I would
really encourage you to upgrade to 2.3.3.


Robert   (robertd@kauri.vuw.ac.nz)

Newsgroups: sci.math.num-analysis
From: schneid@sp94.csrd.uiuc.edu (David John Schneider)
Subject: Re: Exploiting Structure of Hamiltonian Matrices
Organization: Univ. of Ill. Center for Supercomputing R&D
	<SMITH.93Jan22084422@minerva.harvard.edu>
Date: 22 Jan 93 14:28:01

smith@minerva.harvard.edu (Steven Smith) writes:

>
>   By the way, these papers define the symplectic group to be the group
>   of transformations leaving invariant the form
>	  _      _              _
>	x y  + x y  + . . . + x y
>	 1 1    2 2            n n
>    _                                                                  *
>   (y denotes the complex conjugate of y).  This is really the group SO(n);
>   the symplectic group leaves invariant the form
>
>	x y  + x y  + . . . + x y .
>	 1 1    2 2            n n
>
>   I don't know if this matters to you; they do this because the
>   Hermitian pops up in the (complex) Riccati equation.
>
	Neither of these definitions correspond to the usual definition
	of the invariant form for symplectic groups.  For example,
	Gilmore ("Lie Groups, Lie Algebras, and Some of Their Applications",
	J. Wiley, 1974, chapter 2) defines symplectic groups as those
	which preserve a bilinear antisymmetric form such as:

	x y  - x y  + x y   - x   y  + ...
	 1 n	n 1    2 n-1   n-1 2

	The forms mentioned above by Steve Smith are sesquilinear and 
	bilinear, respectively, and both are symmetric.  

	As mentioned by Steve Smith it may be that the authors are really
	interested in the one of the non-compact groups SO^*(2N) or SU^*(2N), 
	the so-called "embedding groups".  The appearance of these groups 
	is reasonable given the close connection between Hamiltonian dynamics 
	and quaternions.

	Another possibility is that the authors are interested in the 
	intersection of the symplectic group with the unitary or orthogonal 
	group.  In this	case both symmetric and antisymmetric forms appear.
	In fact, these two possibilities are related since maximal 
	compact subgroup of SU^*(2N) is the unitary-symplectic group
	USp(2n), and similar relationship holds between SO^*(2N) and U(N).  
	For more details, see chapter 6 in the book by Gilmore mentioned 
	previously.

	In any event, one should realize that it is the invariance of a 
	given bilinear antisymmetric form which crucial to the definition 
	of a symplectic group.  
			

--

		Dave Schneider 

		University of Illinois at Urbana-Champaign 
		Center for Supercomputing Research and Development
		367 Computer and Systems Research Laboratory
		1308 W. Main Street
		Urbana, IL  61801-2307
		MC-264

		phone : (217) 244-0055  
		fax   : (217) 244-1351
		E-mail: schneid@csrd.uiuc.edu
From: holland@geop.ubc.ca (Stephen Holland)
Newsgroups: sci.math.num-analysis
Subject: non-linear least-squares fittin'
Followup-To: sci.math.num-analysis
Date: 22 Jan 1993 21:33:23 GMT
Organization: Geophysics & Astronomy, U.B.C. Vancouver, Canada
Distribution: world
Reply-To: holland@geop.ubc.ca
NNTP-Posting-Host: iridium.astro.ubc.ca


Thanks to everyone who responded.  Most of the suggestions
I received were of the form "look in NETLIB under MINPACK".
The routines LMDIF and HYBRD were mentioned a lot and they
look promising.

steve holland
Newsgroups: sci.math.num-analysis
From: walsteyn@fys.ruu.nl (Fred Walsteijn)
Subject: need references for Runge-Kutta versus Multi-step ...
Summary: where are the methods compared thoroughly ?
Keywords: Runge, Kutta, multistep, efficiency, ODE, PDE
Organization: Physics Department, University of Utrecht, The Netherlands
Date: Mon, 25 Jan 1993 18:04:39 GMT

Dear colleagues,

I am looking for some recent references comparing
the efficiencies of Runge-Kutta and Multistep methods.

My main interest is in the field of time-dependent
pseudo-hyperbolic PDEs describing advection/convection
dominated flows (i.e. diffusion/viscosity very small).
If these PDEs are discretized in space with for example
a finite element method, then a system of ODEs results
which can be solved with either a Runge-Kutta scheme or
a Multistep scheme.

Can you give me some references where the efficiencies
of those schemes are compared thoroughly ?
(Preferably for high spatial resolutions, i.e. very large
 systems of ODEs.)

Please don't give a statement such as ``Runge-Kutta schemes
are too expensive'' without giving a good reference which
proves it.  In fact, section 3.7 of the book:

   E. Hairer, S.P. Norsett, G. Wanner,
      Solving Ordinary Differential Equations I,
      Sringer Verlag, Berlin, 1987

seems to indicate that accurate Runge-Kutta schemes
(such as DOPRI-8) may outperform variable order/stepsize
Multistep schemes for a lot of problems.  Hairer et al apply
both families of schemes to small systems of ODEs as well as
a ``large'' system of ODEs resulting from space-discretization
of a reaction-diffusion problem.

Is DOPRI-8 also more efficient for advection dominated flows ???

I also find Table 7.1 of Hairer et al interesting.  It compares
the storage required for Runge-Kutta and Multistep methods.
The surprising conclusion is that DOPRI-8 is most economical...
Any comments on that ?

Thank you  &  greetings,
-----------------------------------------------------------------------------
Fred Walsteijn                                | Internet: walsteyn@fys.ruu.nl
Institute for Marine and Atmospheric Research | FAX:      31-30-543163
Utrecht University, The Netherlands           | Phone:    31-30-533169
From: lzhao@uoft02.utoledo.edu
Newsgroups: sci.math.num-analysis
Subject: Solving Navier-Stokes Eqn using Penalty Function Method
Date: 27 Jan 93 20:35:47 EST
Organization: University of Toledo, Computer Services

Hi, 
I am solving Navier-Stokes Eqn. using FEM (Penalty-function method) right 
now. I have read lots of papers, but nobody mentioned how they handeled
the force vector. The force vector is

	F1=line or suface integration of(tx)
	F2=line or suface integration of(ty)
where
	tx= 2.0*mu*(du/dx)*nx+mu*((du/dy)+(dv/dx))*ny-p*nx
	ty= mu*((du/dy)+(dv/dx))*nx+2.0*mu*(du/dx)*nx-p*nx
and
   	p=-(penalty number)*(du/dx+dv/dy)

I am now using iteration method to handel this, ie first I assume a velocity
profile, secondly calculate the force vector and then sove for the velocity.
After this , I use the vel. got for the next iteration. But it seems that 
the result does not converge.

Is there anyone can give me some help? 

Regards.

lixin

email: lzhao@uoft02.utoledo.edu	
Newsgroups: sci.math.num-analysis
From: barry@ramsey.cs.laurentian.ca (Barry G. Adams)
Subject: Bessel Fcns of 2nd kind of integer order
Organization: Dept. of Computer Science, Laurentian University, Sudbury, ON
Date: Wed, 27 Jan 1993 20:06:24 GMT

The IMSL special function library doesn't seem to have a routine
for calculating
                       Y  (z)
                         n

where n is an integer and z = x + iy is a complex number. Does
anyone know how to do this or do you know of an available routine?

barry@ramsey.cs.laurentian.ca (Barry Adams)
Newsgroups: sci.math.num-analysis
From: a722756@roper.mc.ti.com (W. Donald Rolph)
Subject: Re: SOME eigenvalues of general matrix
Originator: a722756@roper.mc.ti.com
Organization: Texas Instruments / Attleboro Mass / USA
Date: Thu, 21 Jan 1993 14:16:49 GMT


Sorry for the followup to my folowup.  I just reread and caught your statement
about geenral matrices.  If you mean unsymetric I have saome unpublished work
which extends subspace iteration to the unsymetric case.  I can forward a sketch
of the details if you are interested.
-- 

Regards.
 
Don Rolph  a722756@pan.mc.ti.com WD3 MS10-13 (508)-699-1263
From: caiq@eecs.cs.pdx.edu (Qin Cai)
Newsgroups: sci.math.num-analysis
Subject: Least Square Estimation
Date: 28 Jan 93 03:46:31 GMT
Article-I.D.: pdxgate.6770
Organization: Portland State University, Portland, OR

I have a Least Square Estimation problem which took me a long time but
still couldn't figure out the the method to solve it. I'm sure that 
there is no expilict solution, what I want to know  is the computer
searching algorithm. Could somebody help me?

The problem is to minimize the next function:

       \sum_{s} ||b_{s} - A_{s} *B *c_{s} ||^{2}

where	b_{s}: vector of T by 1,(T is very large, could be thousands), known
	A_{s}: Matrix of T by m, known
	B:     Matrix of m by n,(m > n, m:n could be 100:5), unkown.
	c_{s}: vector of n by 1, unknown.

	\sum_{s} means sum over s, s is the foot note.

Any helpful suggestion is appreciated.
From: goh@nyquist.usc.edu (K.C.Goh)
Newsgroups: sci.math.num-analysis
Subject: Exploiting Structure of Hamiltonian Matrices
Date: 21 Jan 1993 22:17:41 -0800
Organization: University of Southern California, Los Angeles, CA
Distribution: world
NNTP-Posting-Host: nyquist.usc.edu


Does anybody out there know of any numerical routines
for the computation of the eigenvalues of a Hamiltonian
matrix (or the zeros of a Hamiltonian Pencil) which exploit
                                              =============   
the Hamiltonian eigenvalue (zero) structure?
===========================================

For example, are there any numerical routines which produce
Paige and van Loan's Hamiltonian Schur form?


Thanks,

K.C. Goh
From: ramos@engr.LaTech.edu (Alex Ramos)
Newsgroups: sci.math.num-analysis
Subject: Okay, lot's of questions. IS THERE A FAQ ?
Date: 26 Jan 1993 16:56:07 GMT
Organization: Louisiana Tech University
Distribution: inet
NNTP-Posting-Host: atlantis.engr.latech.edu
X-Newsreader: TIN [version 1.1 PL8]


If you happen tp have the FAQ please mail it to me. 

Thanks!


--

/* ramos@engr.Latech.edu                     
                                            
                Fala-se Portugues, tche!     
		English spoken here.
*/ 

Newsgroups: sci.math.num-analysis
From: cai@athena.mit.edu (Liang-Wu Cai)
Subject: Algorithm(s) need for Bessel functions
Organization: Massachusetts Institute of Technology
Date: Mon, 25 Jan 1993 20:14:47 GMT


Dear netter,

 I am in need (badly) of an accurate algorithm Bessel functions of various 
kinds with real argument and integer order. What I need actually is a 
algorithm which is able to provide the result with at least 7 significant 
digits for J_n (z) and Y_n (z) with n <=100 and z <= 100. Please note this
requires a relative error crition, though some absolute critera may be
incorperated with the only purpose to prevent possible underflows. The algoriths
may be in FORTRAN or C, or some easy-to-understant "psuedo-code".

The method in "Numerical Recipes" fails to give out any error information, and
collapes somewhere. I can't find any others. 

Since I need it badly, I may be required to write one for my own. So suggestions
on how to write scuh a function also welcome. 

Thanks in advance.

Please e-mail me at "cai@athena.mit.edu"


Liang-Wu Cai
Newsgroups: sci.math.num-analysis
From: a722756@roper.mc.ti.com (W. Donald Rolph)
Subject: Re: Theory about Fluid-Structure ?
Originator: a722756@roper.mc.ti.com
Organization: Texas Instruments / Attleboro Mass / USA
Date: Thu, 21 Jan 1993 20:45:11 GMT


The proposed method of either Han or myself will couple the navier-stokes
(actually the energy equation is more general I think - comments Han), and the 
dynamic equations of the solid.  It was exactly the elasticity of the fluid 
acting against the dynamic behavior of the soldi which Olsen writes about.
-- 

Regards.
 
Don Rolph  a722756@pan.mc.ti.com WD3 MS10-13 (508)-699-1263
From: lzhao@uoft02.utoledo.edu
Newsgroups: sci.math.num-analysis
Subject: <None>
Date: 27 Jan 93 20:32:44 EST
Organization: University of Toledo, Computer Services

Hi, 
I am solving Navier-Stokes Eqn. using FEM (Penalty-function method) right 
now. I have read lots of papers, but nobody mentioned how they handeled
the force vector. The force vector is

	F1=line or suface integration of(tx)
	F2=line or suface integration of(ty)
where
	tx= 2.0*mu*(du/dx)*nx+mu*((du/dy)+(dv/dx))*ny-p*nx
	ty= mu*((du/dy)+(dv/dx))*nx+2.0*mu*(du/dx)*nx-p*nx
and
   	p=-(penalty number)*(du/dx+dv/dy)

I am now using iteration method to handel this, ie first I assume a velocity
profile, secondly calculate the force vector and then sove for the velocity.
After this , I use the vel. got for the next iteration. But it seems that 
the result does not converge.

Is there anyone can give me some help? 

Regards.

lixin

email: lzhao@uoft02.utoledo.edu
From: lry1219@cfdd40.boeing.com (Larry Yeagley)
Newsgroups: sci.math.num-analysis
Subject: Re: Theory about Fluid-Strucure ? A postscript on domain decomposition.
Summary: fluid-structure interaction & domain decomposition
Date: 22 Jan 93 16:09:54 GMT
Organization: Boeing Computer Services, Seattle - CFD lab


Some additional commments about the fluid-structure interaction problem.

 . The static problem is an excellent candidate for domain decomposition - or
   substructuring as it was known in an earlier incarnation. The solution
   procedure I suggested is a simple form of domain decomposition with separate
   solvers for the fluid and structural domains and user-supplied programs for
   managing the interface conditions.

 . For the dynamic case the structural domain could be represented by its normal
   modes. What happens to the domain decomposition approach isn't clear but it
   might work. Any comments from out there?

 . An alternate approach might be to use Kron's method of tearing with the fluid
   and structural regions solved separately and the results (with corrections)
   pieced together. However, my knowledge of "tearing" is so limited that I
   can't speak reliably about it. Is anyone out there familiar enough with
   "tearing" to comment on this idea?

One of my reasons for this second poster is simply to raise the issue of domain
decomposition in this newsgroup again. A week ago I posted a request for
information about domain decomposition and got virtually no response. The one
response I did get was from within Boeing. Unfortunately, it seems that there is
little or no appreciation of the wide applicability of this approach. Having
said that, I'll take this opportunity to state my request again.

I am looking for domain decomposition information in three areas. To wit:

 . review and/or tutorial articles on domain decomposition methods
 . electronic newsletters devoted to domain decomposition
 . discussions and/or derivations of the Poincare-Steklov interface operators

Is there anyone out there that can provide information on these topics?

Happy trails !!
+---------------------------+--------------------------------------------+
| Larry Yeagley             |     "Life is just a long cul-de-sac."      |
| lry1219@cfdd42.boeing.com |                                            |
+---------------------------+--------------------------------------------+
|  The advice, opinions and mistakes expressed here are my own and       |
|  certainly not Boeing's.                                               |
+------------------------------------------------------------------------+