HDTenEightyP/NetNews huggingface dataset:
Organisation: ECP-Paris France
Date: Sunday, 13 Sep 1992 01:23:10 EDT
From: <COMTET@FRECP12.BITNET>
Newsgroups: sci.math.num-analysis
Subject: fluid mechanics

Is there an algorithm using Finite Elements to simulate the evolution of

a dye with a given difusivity in an uncompressible fluid in two spatial

dimensions ? the equation adimensionned is :

dC/dt + v.gradC = (1/Re.Sc) Laplacian (C)

wher Re and Sc are the Reynolds and the Schmidt numbers.

Such an algorithm exists with finite centered differences and an implicit

scheme in time. (overelaxation method)
Newsgroups: sci.math.num-analysis
From: meglan@mayo.edu (Dwight Meglan)
Subject: Constrained optimization - C code
Followup-To: sci.math.num-analysis
Organization: Orthopedic Biomechanics/ Mayo Clinic
Date: Tue, 15 Sep 92 15:06:42 GMT

I am trying to port some fortran software to C that I wrote several
years ago to solve a problem involving multivariate nonlinear 
constrained minimization. I used a package developed at my old
department (Mech. Eng. at Ohio State Univ.) called OPTPAK. This 
package was derived from another earlier work of the same name. The
optimization code in this package is all in FORTRAN and has alot of
baggage from its long development life. 

I have searched the nets (netlib,archie,etc...) looking for C source
code to use in place of OPTPAK to solve such a problem but have not 
succeeded. I have looked at Numerical Recipes also- but the code for
multivariate nonlinear minimization is unconstrained (at least I think
that is the case :).

So my question is- Could some kind soul out in netland direct me to a
source for such code ? I would prefer something ftp'able but I can scan
a journal article in if the C code is included in it.

thanks for any and all help!

dwight
Newsgroups: sci.math.num-analysis
From: polani@Informatik.Mathematik.Uni-Mainz.DE (Daniel Polani)
Subject: Literature on Voronoi tesselation?
Organization: Computer Science, Johannes Gutenberg-Universitaet
Date: Tue, 15 Sep 1992 19:12:49 GMT

Hi netters,

as the subject line promises, I'm interested on literature on Voronoi
cells. I'm aware of Conway/Sloane's book "Groups, Lattices and Sphere Packings".
Could someone direct me to others, esp. referring to Voronoi tesselations
induced by randomly distributed (that is, not necessarily ordered) points in R^n.
Recent (that is, not only classical) work is very welcome.

Many aTdHvAaNnKcSe

-- 
Daniel Polani   				    
							 
|Institut fuer Informatik          |  Staudingerweg 9    
|Fachbereich Mathematik		   |  6500 Mainz       	 
|Johannes Gutenberg-Universitaet   |  Germany		 


                            
Newsgroups: sci.math.num-analysis
From: mihai@nada.kth.se (Mihai Dorobantu)
Subject: FFT routines in C
Organization: Royal Institute of Technology, Stockholm, Sweden
Date: Tue, 15 Sep 1992 13:06:15 GMT

Hi,

Does anybody know of any public domain
FFT routines in C?

Please reply by e-mail to mihai@nada.kth.se

Thanks,

Mihai Dorobantu



Newsgroups: sci.math.num-analysis
From: adams@chuck.dallas.sgi.com (Charles Adams)
Subject: Contouring Routine from MIT
Organization: Silicon Graphics, Inc.
Date: Thu, 10 Sep 1992 17:55:24 GMT


Gang,

i'm currently using a contouring routine written by Zisk and Brenner
at MIT in July 1968.  it is an excellent contouring program, but i
want to interface it to my own labeling, scaling, and other routines
that are written in C, whereas the contour routine is written in
FORTRAN.  

my question(s).  1.  anyone converted this routine to C?
2.  anyone have a package (PD) that i can get the source code for?

any help greatly appreciated.  i can do it, but at the present time
i don't have that much spare time.  :-)



-- 

   Chuck Adams, K5FO @ 65wpm cw 
   adams@sgi.com
Newsgroups: sci.math.num-analysis
From: kent@kentaurus.dftsrv.gsfc.nasa.gov (James Kent Blackburn)
Subject: least square fitting question
Keywords: l1 l2
Organization: Goddard Space Flight Center
Date: Wed, 9 Sep 1992 13:35:59 GMT

Can anyone provide me with a basic description or even a reference to the  
L1 and L2 techniques for least squares fitting. Please responde to my  
e-mail address (kent@kentaurus.gsfc.nasa.gov) unless you think this is of  
general interest to the group. Thanks in advance!

-Kent Blackburn
kent@kentaurus.gsfc.nasa.gov
Newsgroups: sci.math.num-analysis
From: choup@bionette.cgrb.orst.edu (Ping Chou)
Subject: A series of overflow and underflow
Organization: Biological Computing Consortium, OSU, Corvallis, OR.
Distribution: usa
Date: Sat, 12 Sep 1992 09:06:56 GMT

        I'm trying to evaluate the following series, and wondering if
it can be reduced further (toward some kind of special function).

sum[k=0 to +inf] of [b^k * e^(-b) * P(k+1,a) / K!]

where k is integer, a and b are positive real, e=2.718281828..., and
P() is the incomplete gamma function.

        The only problem is that both a and b can be (and most of the
time in my applications) as large as 5000. Because of this, I have to
put e^(-b) in each term even it has nothing to do with k, and evaluate
log of each term first and then take its exponential,

exp( k*LN(b) - b + LN(P(k+1,a)) - LN(k!) )

otherwise e^(-5000) is effectively zero, and 5000^k will overflow, on
most computers.

        Please let me know if there is better algorithm to evaluate
this series, or if it has an analytical solution. Thanks for your time
and effort.

Ping
Newsgroups: sci.math.num-analysis
From: kerr@ux1.cso.uiuc.edu (Stan Kerr)
Subject: Does anyone have TOMS alg 702?
Summary: Does anyone have a copy of TOMS alg 702?
Keywords: toms alg702 newton truncated
Organization: University of Illinois at Urbana
Date: Tue, 15 Sep 1992 20:35:49 GMT

I'm looking for a copy of algorithm 702 from the March 1992 issue of 
Transactions on Math Software to save a few pennies. Normally I order
these things very promptly and put them on our server ftp.cso.uiuc.edu,
whose TOMS collection is consequently much more up to date than the
netlib's at Oak Ridge or AT&T. However, I missed 702 because of a snafu,
and am wondering if some kind person would make it accessible before I 
have to put in a $100 order.

By the way, I'm aware that the truncated Newton method implemented in 
algorithm 702 is available from netlib as TN, but for my own fussy 
reasons I would like to have the exact version as distributed through
TOMS.
-- 
Stan Kerr    Computing & Communications Services Office, U of Illinois/Urbana
Phone: 217-333-5217      Email: stankerr@uiuc.edu       Vote Marrou!
Newsgroups: sci.math.num-analysis
From: mhumi@theory.TC.Cornell.EDU (Mayer Humi)
Subject: Re: mesh generation for CFD
Organization: Cornell Theory Center
Date: Tue, 15 Sep 1992 03:05:56 GMT

In article <6075@m1.cs.man.ac.uk> fortuna@cs.man.ac.uk (Armando Fortuna) writes:
>Hello everyone,
>
>I am looking for a program which lets you generate/visualize a mesh
>pattern over a domain. I intend to use it for CFD calculations. 
>
>Is there any PD package available? If not, what are the proprietary ones?

This will of interest to others too. PLease post any pointers.
to the net.

-----------------------------------------------------------------
address: Prof. Mayer Humi 	     tel:(508)831-5213
         Dept. of Math,WPI,          e-mail:mhumi@wpi.wpi.edu
         100 Institute Rd.               or tc.cornell.edu
         Worcester,MA 01609,USA
-----------------------------------------------------------------
               
Newsgroups: sci.math.num-analysis
From: kuo@spot.Colorado.EDU (Andy Y.A. Kuo)
Subject: Interpolating 2D and 3D randomly spaced data
Organization: University of Colorado, Boulder
Date: Tue, 8 Sep 1992 16:57:14 GMT

  I am looking for algorithms for interpolating 2D and 3D randomly
spaced data, preferably with error estimation.  Any pointer is
appreciated.

  Andy
From: rh@smds.com (Richard Harter)
Newsgroups: sci.math.num-analysis
Subject: Re: Fourier series approximation
Date: 7 Sep 92 05:25:44 GMT
Reply-To: rh@ishmael.UUCP (Richard Harter)
Organization: Software Maintenance & Development Systems, Inc.

In article <Bu6CKC.6tF@me.utoronto.ca> steinman@me.utoronto.ca (David Steinman) writes:
>kavuri@lips.ecn.purdue.edu (Surya N Kavuri ) writes:

>>  When the data is NOT sampled at regular intervals, how are the fourier
>>  coefficients determined ?

>Well, it may not be pretty (or even that accurate), but I usually just
>integrate the coefficient integrals using a trapezoidal rule.  

There are three cases of interest that I can think of:

(a) The sampling is completely irregular.
(b) The sampling is perturbed from periodic.
(c) The sampling is a replication of a fixed irregular sample.

Case (a) can be handled by a large least squares matrix, but is
practically handled by integration.

Case (b) can be handled by a linear perturbation technique.

Case (c) can be handled by a least squares solution with the the
irregular sample combined with standard equal interval fourier
transform outside the interval.

An example of case (c) is measurements taken during daylight hours
at fixed times every day.

Details are left as an exercise for the reader.
-- 
Richard Harter: SMDS Inc.  Net address: rh@smds.com Phone: 508-369-7398 
US Mail: SMDS Inc., PO Box 555, Concord MA 01742.    Fax: 508-369-8272
In the fields of Hell where the grass grows high
Are the graves of dreams allowed to die.
Newsgroups: sci.math.num-analysis
From: meglan@mayo.edu (Dwight Meglan)
Subject: Num Recipes SVD code
Followup-To: sci.math.num-analysis
Organization: Orthopedic Biomechanics/ Mayo Clinic
Date: Tue, 15 Sep 92 15:10:44 GMT

Some months ago I recall a discussion about there being errors in the
SVD algorithm source code published in Numerical Recipes. Could someone
point me to a location where I can find the corrections ? Either C or
FORTRAN or both will do.

Thanks, dwight
Newsgroups: sci.math.num-analysis,sci.engr,alt.sources.d
From: daveg@synaptics.com (Dave Gillespie)
Newsgroups: sci.math.num-analysis
Subject: Re: Distributed Random Number Generation
Date: 13 Sep 92 08:06:11 GMT
Organization: Synaptics, Inc., San Jose, CA
In-reply-to: maniattb@cs.rpi.edu's message of 12 Sep 92 15:12:58 GMT

In article <h_8yzkk@rpi.edu> maniattb@cs.rpi.edu (Bill Maniatty) writes:
> I have a large distributed stochastic model (runs on MasPar MP-1 with 2,048
> processing elements).  I'm not an expert on random number generation, but
> I need to simultaneously g enerate different ``Random'' sequences on each
> node.

If the nodes must be independent, then it would probably work pretty
well to use one random number generator, say, linear congruential,
to create a sequence of 2048 seeds for a different type of generator,
say additive congruential, running in parallel on the various nodes.
I can't guarantee that this is safe, though, because the biggest
result from random number theory seems to be that nobody knows how
to prove much of anything in it.  :-)

Knuth's _Seminumerical Algorithms_ (volume 2 of _The Art of Computer
Programming_) describes both the generators I mentioned above.

								-- Dave
--
Dave Gillespie
  daveg@synaptics.com, uunet!synaptx!daveg
  or: daveg@csvax.cs.caltech.edu
From: grdg5@cc.usu.edu
Newsgroups: sci.math.num-analysis
Subject: Decomposing Linear Programming problem?
Date: 4 Sep 92 17:56:01 MDT
Organization: Utah State University

Hi there,

I am looking for a solution method to solve a linear programming
problem having the form:

Minimize   c'x + d'y + e'z          ( ' denotes transpose )
 x,y,z
                                                             P1
subject to   Ax + By + Cz <= b
             x >=0 , y >=0, z >= 0

where x, y, and z are vectors of design variables of dimensions
nx, ny, and nz, respectively, and c, d, and e the corresponding
cost vectors.   Since nx, ny, nz, and the number of
inequality constraints are large, I'm interested in a solution method
which decomposes problem P1 into small subproblems for
x, y, and z separately.  However, they are interrelated through a master
problem.

Does anyone run into this kind of problems or have any ideas about such
solution technique?

Thanks in advance.
K. Chompooming
Civil Eng., Utah State U.
Newsgroups: sci.math
From: asimov@wk223.nas.nasa.gov (Daniel A. Asimov)
Subject: Re: My programming experiences
Organization: NAS, NASA Ames Research Center, Moffett Field, CA
Date: Tue, 15 Sep 92 00:46:11 GMT

In article <BuL0HD.6zx@ux1.cso.uiuc.edu> ceblair@ux1.cso.uiuc.edu (Charles Blair) writes:
>
	[...]
>
>   Even though I haven't really learned it, I can see that there is a skill
>in programming that goes beyond a clear understanding of the algorithm one
>is trying to implement.  Perhaps those who are curious about this might
>look at Kernighan's ELEMENTS OF PROGRAMMING STYLE (examples mostly in Fortran).
>If you can guess what the criticisms of the examples will be before reading
>the commentary, you already know quite a lot!  (the examples are taken from
>programming texts, indicating that the authors make mistakes too)

Oh, what the heck, here's something about my programming experiences, too:

I've been programming for roughly 12 years (although not always full-time). 
For quite a while I was a pretty terrible programmer.  I was sloppy and 
undisciplined, and always seeking "shortcuts" that would save me typing
(I was also a terrible typist) but which cost me untold hours of debugging time 
as a result.

Over the years I believe that I have become a fairly decent programmer.  Quite 
far from a super ace hacker, but fairly decent.  How did this happen?  

The answer, I think, is in all the negative feedback I got from the many, many 
bugs that I encountered.  After causing the same bug for the umpteenth time due to 
poor programming discipline, one is motivated to avoid the pain and misery the next 
time.  (I think a lot of wiser people than myself would have heeded much sooner
the good advice found in books such as Kernighan's, rather than learn the hard way.)

Another thing that I believe helps tremendously, is that most of the bugs that
I'm ever going to have, I've already had at least once by now.  So it is far
easier to recognize their symptoms than it was before I had ever seen them.  (Also
important is that, by now, I am not nearly as terrible a typist as I used to be.)

In the early days, after failing to find a particularly tricky bug I would actually 
suspect, on some level, that the machine was being deliberately malicious. This 
attitude was, needless to say, counterproductive.

At some point my experience of programming crossed over from a maddening struggle 
with an incalcitrant and possibly spiteful machine, to a pleasant creative
experience (which necessarily involves a certain amount of drudge work, but well 
worth it).

--Dan Asimov
asimov@nas.nasa.gov

Mail Stop T045-1
NASA Ames Research Center
Moffett Field, CA 94035-1000
(415) 604-4799
Xref: sparky sci.math:11259 sci.physics:14467
From: edgar@function.mps.ohio-state.edu (Gerald Edgar)
Newsgroups: sci.math,sci.physics
Subject: Re: Lebesgue integral (was: Couple of questions
Date: 11 Sep 1992 08:19:12 -0400
Organization: The Ohio State University, Dept. of Math.
NNTP-Posting-Host: function.mps.ohio-state.edu

In article <1992Sep10.173619.24343@galois.mit.edu> jbaez@riesz.mit.edu (John C. Baez) writes:
>In article <18neu6INN32k@function.mps.ohio-state.edu> edgar@function.mps.ohio-state.edu (Gerald Edgar) writes:
>
>>I have been told that the Lebesgue integral is not needed in physics--
>>presumably Riemann integral is enough.  Do you agree?
>
>Last I heard, the Hilbert space of a free particle was L^2(R^3), the
>space of all functions whose absolute value squared is LEBSEGUE integrable.


Now all you have to do is convince the physicists that their
Ph.D. students (at least) should study the Lebesgue theory.
-- 
  Gerald A. Edgar                Internet:  edgar@mps.ohio-state.edu
  Department of Mathematics      Bitnet:    EDGAR@OHSTPY
  The Ohio State University      telephone: 614-292-0395 (Office)
  Columbus, OH 43210             -292-4975 (Math. Dept.) -292-1479 (Dept. Fax)
Newsgroups: sci.math
From: hporopudas@tnclus.tele.nokia.fi
Subject: Re: GOD - THE FINAL CHAPTER
Organization: Nokia Telecommunications.
Date: Tue, 8 Sep 1992 15:36:43 GMT


In article <1992Sep8.001627.90029@vaxc.cc.monash.edu.au>,
kevin@vaxc.cc.monash.edu.au writes:

   ... deleted stuff ...

> In closing, I have also noted another line of argument running - something
> like the following.
> 1. God is existence.
> 2. You can prove the existence of existence in some modified set theory
> (Of course, in normal set theory, you can't.)

   ... deleted stuff ...


   I have here below my text a story about "Spirit of Universe"
   (="Existence") taken from Indian wisdom:

            Hannu.


  "Earth, water, fire, air, ether, thought, reason, and individual
   consciousness are eight fold division of my nature.

   Physical nature that I described is my lowest form of manifestation.
   Another and higher nature of mine is life's principle, by aid of which
   universe is maintained.

   Realize that these two forms the womb for all living beings.
   I'am the beginning of the whole universe and that where the universe
   breaks up.

   There is nothing outside of me. The whole universe depends on me like
   pearls in ribbon.

   I'am taste of water, sun's and moon's radiation, holy OM from all
   veda-books; I'am voice of the space, I'am men's bravery.

   I'am eart's sweet smell and fire's heat, life of all beings, self dicipline
   of ascetics.

   Know that I'am the basic seed of all beings. I'am wise's buddhi, brilliancy
   of celebrated.

   I'am strength of strong, which is not contaminated by lust and passion.
   I'am that love in every beings which is not against dharma.

   Know that purity, passion and lifeless are all from me. These conditions
   do not affect to me, but they are in me.

   Deceived by these three conditions whole this world does not know me,
   I who am above it and eternal.

   This divine illusion, which I bring about and which is based action on
   properties of nature , is difficult to win; but those who resort to me,
   wins this illusion."

  "Whole creation lives and moves under power of mistake, mislead by opposite
   pull - and push - forces."

  "Because I'am above all changeable and unchangeable, I'am known in general
   and acknowledged Highest Spirit in veda books."

  "I penerates whole this world in form of without manifestation; all beings
   are living in me, but I'am apart of them."

  "I send warm; I hold back rain and send rain; I'am immortality and death;
   I'am existing and also not existing."

  "Meditate that like to all around moving storm wind is binded to the space,
   likewise all beings are depended on me."

         (Indian wisdom, About God and nature, rough translation)

Organization: Doctoral student, Mathematics, Carnegie Mellon, Pittsburgh, PA
Newsgroups: sci.math
Date: Tue, 15 Sep 1992 11:05:55 -0400 
From: "Vincent J. Matsko" <vm0h+@andrew.cmu.edu>
Subject: Hyperspherical triangles...

I am interested in being able to calculate the areas of spherical
triangles, where the sphere may have arbitrary dimension.  I am
acquainted with the formula in 3 dimensions, and the proof of this
formula can easily be extended to ODD dimensions.  But, I am afraid, I
am stuck when it comes to even dimensions.

Anyone have any insights/references?

For all those linear algebraists/probabilists, here is an equivalent
formulation:

Given n linearly independent vectors (v_1, v_2, ... v_n) in R^n, and
given the standard inner product on R^n: Given a vector u in R^n, what
is the probability that the inner product of u with v_i is positive for
all 1 <= i =< n?

Vince Matsko
Newsgroups: sci.math,comp.lang.misc,comp.lang.fortran,comp.std.c,comp.lang.c
From: prener@watson.ibm.com (Dan Prener)
Subject: Re: Scientists as Programmers (was Re: Small Language Wanted)
Date: Mon, 14 Sep 1992 06:45:10 GMT
Disclaimer: This posting represents the poster's views, not necessarily those of IBM
	<MEISSNER.92Sep11164441@curley.osf.org>
	<BuJ4Es.49w@mentor.cc.purdue.edu>
Organization: IBM T.J. Watson Research Center, Hawthorne, New York


In article <BuJ4Es.49w@mentor.cc.purdue.edu> hrubin@pop.stat.purdue.edu (Herman Rubin) writes:

[... deletion ... (topic was obtaining long long product of two longs) ]

>                                                      And it still is
>not quite adequate.  One should be able to have the option of overloading
>the * operator so that if c is long long, and a and b are long, this can
>be written as c = a * b.  

While that could be done, it goes very much against the spirit of most
languages' expression evaluation, in which a * b has a value that is
well defined without reference to the context in which it is used, in
this case the type of the target of the assignment.
--
                                   Dan Prener (prener@watson.ibm.com)
Newsgroups: sci.math
From: sasmb@carroll.unx.sas.com (Miguel Bamberger)
Subject: Humanistic Math Network
Originator: sasmb@carroll.unx.sas.com
Date: Wed, 9 Sep 1992 14:51:22 GMT
Organization: SAS Institute Inc.


Does anyone know who publishes the Humanistic Mathematics Network
Newsletter?
-- 
Miguel Bamberger   | Mr Cooper's Law: "If you do not understand a particular
Austin Tech Pubs   | word in a piece of technical writing, ignore it.
                   | The piece will make perfect sense without it."
From: ara@zurich.ai.mit.edu (Allan Adler)
Newsgroups: sci.math
Subject: AMS Elections
Date: 15 Sep 92 21:17:36 GMT
Article-I.D.: camelot.ARA.92Sep15161736
Distribution: sci
Organization: M.I.T. Artificial Intelligence Lab.


AMS members are currently being asked to vote on candidates for offices in
the AMS, including: vice-president, member-at-large of the council,
trustee, editorial boards committee, nominating commitee.

Members are given information about each candidate, such as:
title, institutional affiliation, where and when he/she got his/her degree ,
AMS committees the candidate has been on, selected publications, other
information (usually other public service) and perhaps a statement of
where they stand on various issues or what they propose to do.

It is natural, when reading some of the things that they propose to do,
whether one agrees with them or not, to ask what authority they will
be given to make the changes that they say they will work for. This
in turn raises a natural question the answer to which I do not know
and do not recall being included in any information that I have ever received 
from the AMS, namely:

How is the AMS constituted and what exactly do its various elements do
and what are the powers and responsibilities of the people who hold
various offices? And how much of their time is actually taken up
with these activities?

This information does seem pertinent to any attempt to evaluate
the proposals and qualifications of the candidates.

Would anyone like to fill in the details?

Allan Adler
ara@altdorf.ai.mit.edu
Newsgroups: sci.math
From: pratt@Sunburn.Stanford.EDU (Vaughan R. Pratt)
Subject: Re: 3 space terahedron-packing
Organization: Computer Science Department,  Stanford University.
Date: Sun, 13 Sep 1992 06:26:08 GMT

In article <BuCLKs.Mx2@acsu.buffalo.edu> kriman@acsu.buffalo.edu (Alfred M. Kriman) writes:
>ObAncients:  I think the classical proof that pyramid/cone volume is
>base_area times height / 3 was based on a decomposition like this.

Why limit the ancients to "floor faces"?  You get a similar argument
merely by dropping "floor" and allowing all six faces.  If you now
partition the points of the unit cube by grouping together those points
nearest a given face you get six square pyramids.  (Another
description:  each pyramid has base one face of the cube and apex the
center of the cube.)  Each pyramid has volume 1/6, base area 1, and
height 1/2, yielding the magic factor 1/3.

-- 
======================================================| God found the positive
Vaughan Pratt   pratt@cs.Stanford.EDU   415-494-2545  | integers, zero was
======================================================| there when He arrived.