HDTenEightyP/NetNews huggingface dataset:
From: mroussel@alchemy.chem.utoronto.ca (Marc Roussel)
Subject: Re: The Real Meaning of Efficiency?  (Re: Serious Programming, etc.)
Organization: Department of Chemistry, University of Toronto
Date: Fri, 20 Nov 1992 18:36:48 GMT

In article <1ej8dvINN3u2@agate.berkeley.edu> fateman@peoplesparc.Berkeley.EDU
(Richard Fateman) writes:
>At Berkeley, we haven't taught Fortran in CS for many (20) years.  There
>is a Fortran intro course in engineering, taught by engineering faculty.
>But the main upper division scientific computing for engineers course
>is taught using Matlab, although there is some (I think) fortran.

     There are several constraints in designing a CS/programming curriculum
for scientists and engineers.  One of them is that most of your students
are unlikely to take more than two half-courses because that is all that
their departments mandate.  A worthy approach might be to start out with a
half-course in algorithms and basic theory, perhaps even without assigning any
programming exercises.  (In other words, don't make them learn ANY
programming language.  Implementation details too often detract from learning
in introductory CS courses.)  Let the students learn about algorithms by
using their own brains.  In a second half course, introduce a handful
of programming environments and design programming exercises that will
require interaction of these environments.  For instance, you might
choose Fortran, Maple and Matlab.  Maple does a symbolic computation,
generates Fortran code which is compiled and produces some output which
is passed to Matlab for visualization.  (The whole process could
obviously and naturally be spread over several assignments.)  That's the
way scientists really work and there is no sense pretending that any one
system can do everything.

>In article <By0q94.9p9@news.cso.uiuc.edu> Richard J. Gaylord
><gaylord@ux1.cso.uiuc.edu> writes:
>>Its totally clear that most cs departments don't have
>>the faintest idea what non-cs people want or need to know about
>>programming. 
>>This can be seen from the recent move at many places from
>>FORTRAN to C as the first language. 
>
>False, at least for my department.  We don't teach C first, and we certainly
>don't push C as a language for scientific computing.

     Perhaps, but some CS departments are doing this, even to their own
students.  The truth is that neither Fortran nor C is a wonderful
teaching language.  (Fortran is too restrictive and C is too
permissive.)  Fortran in combination with other tools might not make a
bad combination however.  The students can always learn C later.

>>the best thing that could happen to the teaching of programming to tech
>>people would be to use mathematica to do it.

     Why Mathematica in particular?  More importantly, why Mathematica
alone?  Scientific computation almost never involves only one language
or tool anymore.  I have no real objection to Mathematica being a part
of the curriculum, but it seems silly to not teach the students to be
flexible and use whatever tools seem most appropriate.

				Marc R. Roussel
                                mroussel@alchemy.chem.utoronto.ca
Newsgroups: sci.math.symbolic
From: katherle@daisy.uwaterloo.ca (Kate Atherley)
Subject: Re: new version of Maple for the Mac?
Organization: University of Waterloo
Date: Fri, 20 Nov 1992 14:26:17 GMT

In article <1992Nov19.132032.16499@sarah.albany.edu> hibrown@sarah.albany.edu (Herb Brown) writes:
>In article <BxxK58.DtH@watdragon.uwaterloo.ca> katherle@daisy.uwaterloo.ca (Kate Atherley) writes:
>When will release 2 be available for the Amiga?

End of first quarter of 1993.  For more information, please
contact info@maplesoft.on.ca.

Kate
Waterloo Maple Software Technical Support
support@maplesoft.on.ca

Newsgroups: sci.math.symbolic
From: Richard J. Gaylord <gaylord@ux1.cso.uiuc.edu>
Subject: Re: Help ! Mathematica and Maple Road Test
X-Xxdate: Wed, 18 Nov 92 14:17:20 GMT
X-Useragent: Nuntius v1.1.1d12
Organization: University of Illinois
Date: Wed, 18 Nov 1992 20:15:42 GMT
X-Xxmessage-Id: <A73000F04D019B11@mm-mac17.mse.uiuc.edu>

urghhh !!!
Newsgroups: sci.math.symbolic
From: jaffer@zurich.ai.mit.edu (Aubrey Jaffer)
Subject: Differentiation
Organization: M.I.T. Artificial Intelligence Lab.
Date: Mon, 16 Nov 1992 00:57:16 GMT

This paper is from the Numerical Optimisation Centre of Hatfield
Polytechnic, ENGLAND.  Principal author is L.C.W. Dixon.  Premise is:

     "In most optimisation algorithms it is assumed that it is possible
   to calculate both the objective function F(x), x [in] R^n and its
   gradient vector at any requested value of x.  Second order methods are
   well known that could utilise the Hessian matrix DEL^2F(x) if this
   could be computed efficiently, however traditionally such algorithms
   have not been favoured for problems with n>5 because of the difficulty
   of analytically coding the expressionf for DEL^2F for complicated
   industrial problems.
     "In a typical industrial problem the code necessary to compute F(x),
   given x, may well consist of 200 lines of FORTRAN and involve 1000
   arithmetic steps; even if n is realatively small (say n=20).
     "The task of deriving formula for the n values of the gradient for
   such an objective function is daunting and may well take man-days of
   effort...  Most symoblic differentiation codes such as that included
   in REDUCE and MACSYMA are defeated by the length of such a task
   Griewank [1988]."  

Has some reader of this newsgroup worked on such a problem?  I don't
think of differentiation as a hard problem.  It seems to me that the
derivative of such a problem will be large no matter how it is arrived
at.  What am I missing?
From: mstankus@oba.ucsd.edu (Mark Stankus)
Newsgroups: sci.math.symbolic
Subject: Inequalities posting: Convert1.m
Date: 20 Nov 92 19:34:37 GMT
Organization: Mathematics @ UCSD

(* :Title: 	Convert1 // Mathematica 2.0 *)

(* :Author: 	Mark Stankus (mstankus).
                Based on the work of David Hurst (dhurst)
                in the file NCTools.m 
*)

(* :Context: 	Convert1` *)

(* :Summary:
		Convert1 is similar to Convert1, but only works
                for commutative expressions. Convert1 does
                not depend on any NCAlgebra code.
*)

(* :Alias:
*)

(* :Warnings: 
*)

(* :History: 
   :8/26/92     Wrote code. (mstankus)
   :10/18/92    Adapted Convert1 from Convert2. (mstankus)
*)
BeginPackage["Convert1`"];

Clear[Convert1];

Convert1::usage = 
     "Convert1[expr] is a variant of Convert1[expr] which is \
      recursive and follows a slightly different ordering.";
 
Begin["`Private`"];

(*
      Change input given in the wrong format to the
      correct format with a head of Equal.
*)
Convert1[x_Plus] := Convert1[x==0];

Convert1[x_Rule] := Convert1[x[[1]]==x[[2]]];

Convert1[x_RuleDelayed] := Convert1[x[[1]]==x[[2]]];

Convert1[x_List] := Map[Convert1,x];

Convert1[True] := 
Module[{},
    Print["Warning from Convert1: Converting True"];
    Return[0->0]
];

Convert1[False] := 
Module[{},
    Print[" :-( Severe Warning from Convert1: Converting False"];
    Abort[];
    Return[0->0]
];

(* 
      The important code.
*)
Convert1[x_Equal]:= Convert1[Equal[x[[1]]-x[[2]],0]] /; Not[x[[2]]===0]

Convert1[x_Equal]:=
Module[{expr,expr2,orderedlist,left,right,coeff,
        var,temp},
     expr = Expand[x[[1]]];
     If[Head[expr]===Plus,expr2 = Apply[List,expr];
                         ,expr2 = {expr};
     ];
     orderedlist = Sort[expr2];
     left = orderedlist[[-1]];
     right = -expr + left;
     If[Head[left]==Times, coeff= left[[1]];
                           left = left/coeff;
                           right = right/coeff;
     ];
     var = Unique[];
     temp = right/.left->right;
     If[Not[FreeQ[temp,var]], 
           Print["Using the rule ",left->right];
           Print["leads to an infinite loop."];
     ];
     Return[left->right]
] /; x[[2]]===0

End[];
EndPackage[]
-- 
mstankus
mstankus@oba 
Newsgroups: sci.math.symbolic
From: santas@inf.ethz.ch (Philip Santas)
Subject: Re: Serious Programming (was: Re: MAPLE resources reccomendation)
Organization: Dept. Informatik, Swiss Federal Institute of Technology (ETH), Zurich, CH
Date: Tue, 17 Nov 1992 21:31:30 GMT


In article <1eb8j4INNld2@agate.berkeley.edu> fateman@peoplesparc.Berkeley.EDU (Richard Fateman) writes:
>
>So for serious programming, I'd put Mathematica near the end of the list.
>For non-serious programming, it is much more appealing, especially
>if you can exercise some restraint in how much of it you use, and you
>are able to avoid questions of scope, evaluation, and limited data
>structure choices.

I would not agree that a _rich_ set of data structures provided by the system's
kernel is an indication of the quality of the programming environment.
Th argument here is the same as to whether the system should provide many
built-in functions.

For instance, Smalltalk and ML (the former for OOP, the latter for FP), provide
a small but _proper_ set of built-in structures; the rest can be implemented 
in the language itself, in the form of Classes (in Smalltalk) and Structures/Types 
(in ML). It is possible to write _very_ efficient code even for Big Integers in 
such environments.

The basic concepts here are _adequate_ language constructs, type inferencing
and (static/dynamic) compilation capabilities.

Philip Santas

  "In an evolving universe those who stand still are really moving backwards"
--------------------------------------------------------------------------------
email: santas@inf.ethz.ch				 Philip Santas
Mail: Dept. Informatik				Department of Computer Science
      ETH-Zentrum			  Swiss Federal Institute of Technology
      CH-8092 Zurich				       Zurich, Switzerland
      Switzerland
Phone: +41-1-2547391
      




Newsgroups: sci.math.symbolic
From: Richard J. Gaylord <gaylord@ux1.cso.uiuc.edu>
Subject: Re: Serious Programming
X-Xxdate: Fri, 20 Nov 92 12:54:19 GMT
X-Useragent: Nuntius v1.1.1d12
Organization: University of Illinois
Date: Fri, 20 Nov 1992 18:52:37 GMT
X-Xxmessage-Id: <A732907B8F029B19@mm-mac25.mse.uiuc.edu>

Subject: Re: Serious Programming
From: George J. Carrette, gjc@mitech.com
Date: 20 Nov 92 09:25:59 GMT
In article <3699@mitech.com> George J. Carrette, gjc@mitech.com writes:
> you just -have- to be made to look
>foolish
>
Only somebody that has been living in a cave would not be able to
>figure .......

==============

i won't bother to respond to this jerk but he should learn some net
etiquette.  personal attacks are totally unacceptable.
Newsgroups: sci.math.symbolic
From: scavo@cie.uoregon.edu (Tom Scavo)
Subject: Re: New UBASIC coming out?
Organization: University of Oregon Campus Information Exchange
Date: Fri, 20 Nov 92 21:16:37 GMT

This really doesn't belong in sci.math.symbolic, but...

In article <By0JqF.DpM@world.std.com> mrd@world.std.com (Mitchell R Dickerman) writes:
>Does anyone know if/when UBASIC 9 will be coming out? What will be the new
>features?

Does UBASIC do graphics yet?  This is/was one of its
most serious flaws, imho.

-- 
Tom Scavo
scavo@cie.uoregon.edu
Newsgroups: sci.math.symbolic
From: monagan@inf.ethz.ch (Michael)
Subject: Re: MAPLE: Reading list of points from external file
Summary: Reading data into Maple
Organization: Dept. Informatik, Swiss Federal Institute of Technology (ETH), Zurich, CH
Distribution: sci.math.symbolic
Date: Tue, 17 Nov 1992 17:14:35 GMT


The question was asked how to read data from an external file into Maple.
There are no facilities in Maple V for reading arbitrary data.  The comment
by one user that Maple should not call itself a programming language if
it cannot read data is fair comment.  What you must do is make the
data that you want to read into Maple valid Maple input.  I.e. if you
have numbers on a line separated by spaces you must insert commas between
them and assign them to a variable, and add a semicolon or colon at the end.
I.e. make the input file look like

   DATA := 2.3, 3.4, 5.6 ;

Once you have read the file, you can put the sequence in a list or array
and continue.  The new version, Release 2, has the equivalent of C's scanf,
also printf, and some other utilities that make reading and writing data
to files much easier to do.  I wrote an article on how to read and write
data from files in the share library.  It's the
file maple/5.0/tex/program.tex which you can get from
anonymous ftp at daisy.uwaterloo.ca

Michael Monagan
From: kaufmann@ifm.ethz.ch (Stephan Kaufmann)
Newsgroups: sci.math.symbolic
Subject: German Mathematica Book
Keywords: Mathematica
Date: 16 Nov 92 09:28:59 GMT
Reply-To: kaufmann@ifm.ethz.ch (Stephan Kaufmann)
Organization: Swiss Federal Institute of Technology - Inst. of Mechanics

Announcement/Ankuendigung
-------------------------

The first German Mathematica book:

Mathematica als Werkzeug: Eine Einfuehrung mit Anwendungsbeispielen
Stephan Kaufmann
Birkhaeuser, 1992.
ISBN 3-7643-2832-0
408 Seiten, SFr 48.-/DM 54.-

---

This book is intended as an introduction for engineers, scientists and
applied mathematicians. It covers the full range of Mathematica, from
symbolic and numeric calculations to programming. The investigations
are motivated by some nontrivial examples.

---

Dieses Buch ist eine Einfuehrung in Mathematica, v.a. gedacht fuer
Ingenieure, Wissenschaftler(innen) und angewandte Mathematiker(innen).
Mit wiederholt aufgegriffenen Anwendungsbeispielen wird gezeigt,
wie sich auch schwierigere Probleme mit wenigen Eingabezeilen loesen lassen.

Ein erster, ausfuehrlicher Teil behandelt die breiten Faehigkeiten von
Mathematica. Danach wird seine Funktionsweise genauer untersucht und
erlaeutert. Darauf basiert im dritten Teil eine Diskussion von
verschiedenen Aspekten und Techniken der Programmierung.


--------------------------------------------------------------
Stephan Kaufmann                          kaufmann@ifm.ethz.ch
Institute of Mechanics
ETH Zentrum, HG F38.4                     Tel: +41 1 256 23 09
CH-8092 Zurich, Switzerland               Fax: +41 1 262 05 33
--------------------------------------------------------------
Newsgroups: sci.math.symbolic
From: PEARCES@IBM3090.BHAM.AC.UK
Subject: (None set)
Date: Thu, 19 Nov 1992 12:10:00 GMT
Organization: The University of Birmingham, United Kingdom

First of all may I express my utmost thanks to Kate et al.
Unfortunately the above does not help me with my problem that much.
Therefore I will try to explain it more fully.
Sadly this will mean using terms and concepts with which I am still
as yet not fully comfortable.

Firstly my original expression contains square roots.
These are multi-valued and hence we have 2 Rieman sheets for the
rooted parts of the expression.
Since there are 2 of these does this mean that the expression without
the ^2 has 4 Rieman sheets and after squaring this expression
has 2?
I have worked out by hand that the `spurious' roots quoted above
correspond to the expression when we choose the negative root
for one of the square roots and the positive for the other.
This would mean that the `spurious' roots are on a different Rieman
sheet to that normally evaluated by MAPLE.
It is this situation I am most interested in since it has physical
significance in the problem I am tackling.

So the question in a nut shell is how to change the original expression
so that it corresponds to the `spurious' roots and then eliminate the
zero to find the remaining function (or just its value at the zero
if this is not possible).
Since this is to form part of a problem solving system
I need a routine to do this automatically.
Any further help would be greatly appreciated.
Yours Gratefully,
Stephen Pearce.
P.S. I am using MAPLE 4.2 on an IBM3090 and so did not fully understand
the MAPLE V syntax in the last message.
Newsgroups: sci.math.symbolic
From: katherle@daisy.uwaterloo.ca (Kate Atherley)
Subject: Re: MAPLE availability.
Organization: University of Waterloo
Date: Wed, 18 Nov 1992 21:13:33 GMT

In article <16NOV92.23604722.0071@VM1.MCGILL.CA> B7NS <B7NS@MUSICB.MCGILL.CA> writes:
>I was curious if anyone could tell me if the newest version
>of MAPLE is available for Atari ST/TT series of computers,
>and what is the price for higher education students.

Maple V Release 2 for the Atari ST computers will be available
at the end of the first quarter 1993.  

For more information, please contact info@maplesoft.on.ca

Kate
Waterloo Maple Software Technical Support
support@maplesoft.on.ca
Newsgroups: sci.math.symbolic
From: Richard J. Gaylord <gaylord@ux1.cso.uiuc.edu>
Subject: Re: Serious Programming
X-Xxdate: Wed, 18 Nov 92 04:55:54 GMT
X-Useragent: Nuntius v1.1.1d12
Organization: University of Illinois
Date: Wed, 18 Nov 1992 10:54:13 GMT
X-Xxmessage-Id: <A72F7D5AD4029B11@mm-mac17.mse.uiuc.edu>

first of all, my apologies for the intemperate use of the phrase "
serious programming". 
that was just a response to the initial  ridiculous (in my opinion)
comment  that Maple is somewhat more powerful [than Mathematica] in just
about every way.  Mathematica's only advantages are in pattern matching. "

obviously Maple is a serious cas [ and release 2 looks like its going to
be really nice]  and since most of it is written in the Maple language 
the Maple language must be serious, indeed.
==================
let's bring some focus to this thread.

i  am comparing  cas languages ONLY in terms of their ability to do 
functional programming . I am excluding graphics, algebraic manipulation,
numerics, etc.  i understand that there are many other issues involved in
comparing cas languages but this is the issue i am competent to discuss.

i maintain that mathematica does the best job of bringing the functional
style of programming into scientific computing. (no one is using  ML or
Scheme or Haskell or FP to do scientific computing ). 

here are the good 'functional' things i find in the Mathematica
programming language 

(1)  mathematica's use of fully spelled out english names for its
built-in functions and its use ofa  mathematical equational style  is
superior to the syntax of other  languages  (with the exception of APL
whose runic symbols and one way evaluation  scheme are especially
appealing ). 

(2) mathematica  definitely has one of the most sophisticated pattern
matchers around. it should not be dismissed as unimportant. it is an
incredibly useful programming tool.

(3) the use of a rewrite rule system, while certainly problemmatic, is
very useful.

(4) while the built-in list manipulation and higher-order functions are 
not a part of functional programming per se, they are extremely useful to
have save me considerable time in writing programs 

all of these 4 specific features are part of the 'functional'  style of
programming [ i know that what is a functional feature is often argued
but these features above are common to most  functional languages eg.,
ML)]  and i don't think that any other  language (cas or otherwise) comes
close to mathematica in providing these specific functional programming
tools for  scientific computing. 

am i wrong in saying this?
Newsgroups: sci.math.symbolic
From: abond@rvgs.vak12ed.edu (Andrew H. Bond)
Subject: Re: Three-sided coin (ANSWER)
Organization: Virginia's Public Education Network (Roanoke)
Date: Fri, 20 Nov 92 10:17:14 GMT

jac@ds8.scri.fsu.edu  writes:
> In article <1992Nov19.085455.11218@rvgs.vak12ed.edu> abond@rvgs.vak12ed.edu (Andrew H. Bond) writes:
> >matmcinn@nuscc.nus.sg  writes:
> >> 
> >> Is there any country in the world that issues such thick coins so we
> >> can check this out experimentally?        ... 
> >
> >If you are really interested in testing this solution, why not
> >just get some superglue and glue a bunch of coins together in a
> >stack. Superglue forms very thin, rigid layers of adhesive  ... 
> >
> >Andrew H. Bond, Roanoke Valley Graduate Center
> 
> Good for you!  Someone finally proposes an actual *experiment* to look 
> at this problem.  For a long while I thought this was sci.metaphysics. 
> 
> Must still be a theorist, however.  Coins are not thin enough to get 
> an accurate answer this way, but it is a good start to find out the 
> parameters of the problem.  Certainly the easiest approach is to 
> get some 3/4" dowel and use a miter saw to chop it into a variety 
> of lengths (say 5 copies of each length), and enlist some school kids 
> or undergrads to take data.  Better yet, go into the shop and cut up
> some nice steel rods and build a device to so the flips "perfectly" ...
> 
> --
> J. A. Carr                                    |  "The New Frontier of which I  
> jac@gw.scri.fsu.edu                           |  speak is not a set of promises

I envision this as one of those "try this at home" experiments.
Not every undergrad has a miter saw, dowel rods (I would
suspect the accuracy of this method due to the elasticity
differences, and the deformation of the corners due to the
softness of the wood), In his dorm room, to say nothing of
thick steel rods, and the bandsaws to cut them accurately. With
coins it is very easy to aquire the materials, and likewise to
achieve reasonable accuracy, all in the comfort of ones
dormroom. BTW, the shops at most universities are somewhat
hesitent to allow students to use their equipment these
days--prob. due to idiotic legal hassles over some student who
cut his hand off, then sued the U.--just my $0.02 worth--AHB.
-- 
Andrew H. Bond, Roanoke Valley Graduate Center
From: arno@cwi.nl (Arno Siebes)
Newsgroups: sci.math
Subject: Re: jump in price of journals
Date: 19 Nov 92 13:41:04 GMT
Organization: CWI, Amsterdam


Dave Joyce writes:
>We've had to cut subscriptions to journals because of the big price hike
>primarily in European journals.
The fact that especially European journals became much more expensive
suggests that the plunge of the dollar may have had something to do
with this.

Arno
From: rick@daffodil.tymnet.com
Newsgroups: sci.math
Subject: Re: Undergraduate textbooks
Date: 23 Nov 92 20:10:05 GMT
Organization: BT North America, San Jose, CA

I have taught many college  and high school  students  calculus.  Many
of them are shakey  in their algebra  skills.  Sure they passed the class,
but it's been a whole semester since then.  The result is that many of them 
complain about the calculus teacher "going too fast" or "how did he get that
answer?" . It's because they aren't "fluent" enough in algebra (not to mention
basic math concepts such as adding unlike fractions) I believe that they 
should be required to do the alebraic simplification because it helps reinforce 
and strengthen their rapidly fading memories.  

Learning math is like learning a foreign language, you have to con-
stantly use (practice) what you have learned or it will go away.   One of 
the problems with college courses is that you take them  and forget them 
after finals.  Math stayed with me through the years because each course
used all the courses before it. 

In teaching mathematics, you have the opportunity to show the student
how he/she can use calculus to add on tho their already proven ability
in algebra.  It should not be taught as a separate concept because it is 
simply a continuation in the process of being able to "speak" the language
of math!







---------------------------------------------------
"In the country of the blind, the one-eyed men are kings."
From: steiner@andy.bgsu.edu (Ray Steiner)
Newsgroups: sci.math
Subject: Re: 1+1/2+1/3+1/4+...+1/n
Date: 19 Nov 92 17:45:00 GMT
Article-I.D.: andy.Bxz5B2.KMG
Organization: Bowling Green State University B.G., Oh.

rouben@math9.math.umbc.edu (Rouben Rostamian) writes:

>In article <92324.132329K3032E2@ALIJKU11.BITNET> Mutter Christoph Johannes <K3032E2@ALIJKU11.BITNET> writes:
>>I've a problem. I have to calculate the sum 1+1/2+1/3+1/4+...+1/n.
>>The result should be 100. But my computer is far too slow, to solve this
>>problem. I need the index n when the sum > 100.0
>>And that exactly.  Has anyone calculated this? (Perhaps on a CRAY|) ?

>Here is a program that you may find useful.  It has been completely
>debugged on my personal cray.

>sum = 0
>for k=1 to 10^44
>   sum = sum + 1/k
>end
>print sum

Is this a joke? (Flames kept under glass for now!)
Ray Steiner
-- 
steiner@andy.bgsu.edu
Newsgroups: sci.math.stat