HDTenEightyP/NetNews huggingface dataset:
From: dharr@sol.UVic.CA (D.A. Harrington)
Subject: Using expand on Taylor series in Maple
Keywords: Maple, expand
Organization: University of Victoria, Victoria, B.C. CANADA
Date: Tue, 28 Jul 92 21:35:00 GMT

I seem to be unable to get "expand" to work on the substituted taylor
series below, although simpler examples appear to work
Suggestions much appreciated - please reply to the newsgroup or
email to dharr@uvvm.uvic.ca
Maple is running under CMS on an IBM 3090

    |\^/|     Licensed for use at: University of Victoria
._|\|   |/|_. WATCOM Products, Inc.
 \  MAPLE  /  Version 4.2
 <____ ____>  For on-line help, type  help();
      |
>
t:=taylor(exp(x),x,3);
                                            2      3
                          t := 1 + x + 1/2 x  + O(x )

>
subs(x=a+b,t);
                                            2            3
                     1 + a + b + 1/2 (a + b)  + O((a + b) )

>
expand(");
                                            2            3
                     1 + a + b + 1/2 (a + b)  + O((a + b) )

>
#why didn't it expand? this works:
#why didn't it expand? this works:
>
s:=y^2 + O(y^3);
                                      2      3
                                s := y  + O(y )

>
subs(y=c+d,s);
                                    2            3
                             (c + d)  + O((c + d) )

>
expand(");
                          2            2            3
                         c  + 2 c d + d  + O((c + d) )

>
#so is there something special about Taylor series?
#so is there something special about Taylor series?
>
quit;
words used=12949, alloc=11176, time=.122
Newsgroups: sci.math.symbolic
From: sibley@math.psu.edu (David Sibley)
Subject: galois problem
Reply-To: sibley@math.psu.edu
Organization: Dept. of Mathematics, Penn State University
Date: Mon, 27 Jul 1992 19:49:11 GMT


In the following:  What does the error message mean?  Why won't maple
find the Galois group?  A change of variables does work to allow the
Galois group to be computed, but I don't think I should have to do
that.  (Anyway, how would I know what change of variables would work?)

Environment: Sparcstation running SunOS 4.1.1.

David Sibley
sibley@math.psu.edu
-----------------------------------------------------
    |\^/|      MAPLE V
_|\|   |/|_.  Copyright (c) 1981-1990 by the University of Waterloo.
 \  MAPLE  /   All rights reserved.  MAPLE is a registered trademark of
 <____ ____>   Waterloo Maple Software.
      |        Type ? for help.
> f:=1+2*x+3*x^2+4*x^3+5*x^4+6*x^5+7*x^6;
 
                                  2      3      4      5      6
                f := 1 + 2 x + 3 x  + 4 x  + 5 x  + 6 x  + 7 x
 
> galois(f);
Error, (in unknown) division by zero
>


Newsgroups: sci.math.symbolic
From: freek@cv.ruu.nl (Freek Beekman)
Subject: Non-linear fitting with Mathematica.
Date: Thu, 23 Jul 1992 09:06:24 GMT
Distribution: sci.math.symbolic
Organization: University of Utrecht, 3D Computer Vision Research Group
Keywords: curve fitting, least squares approximation. non-linear

Hello,

who knows how to do a non-linear fit with Mathematics. I want to fit a
non-linear function(A produkt of error-functions, Gaussians and
exponential functions with the parameters to be fitted also in the
argument of the functions). I think i cant reduce the function to a
linear form as is shown in the Mathematics book. I have nine parameters
to fit, and about 2000 measured points. The fit has to be a least square
fit.   If it is possible I want to know how I can have speed up this fit
routine, because I feel it can take a lot of time.  The derivatives are
large formulas.  Therefore it could take a long time to evaluate them in
the
fitroutine, and therefore it would be better to take a fit routine that
doesnt use derivatives during the fit.

Thanks in advance for your reply,

Freek.

--
     -   Freek J. Beekman -

Department of Radiology and Nuclear Medicine/3D ComputerVision
Utrecht University Hospital, Room E02.222
Heidelberglaan 100
3584CX Utrecht
The Netherlands
Phone +31-30-506711/506053
Fax   +31-30-513399
email freek@cv.ruu.nl



Newsgroups: sci.math.symbolic
From: saxena@cs.albany.edu (Tushar Saxena)
Subject: Mathematic Maual or Help on some functions
Originator: saxena@sutra.albany.edu
Keywords: Mathematica.
Organization: The University at Albany, Comp. Sci. Dept.
Date: Wed, 22 Jul 1992 21:14:59 GMT


I have a file which is in Mathematica and we here only have Maple.
I am thus trying to rewrite that file in Maple. There are certain
functions in Mathematica that I am having problem understanding. It
may be noted that I do not have any maual etc to go by. I am just
looking at the Mathematica commands and trying to make whatever I can
of them. Obviouly I could not get very far!

I would like to know if there is any manual for mathematica in some
free domain. If not, can somebody please mail it to me? If none of
the above are possible, then please tell me what the following commands
could mean :

1]  <<roots.m;

2] trootlist=Table[Join[roots[[i]], {1}], {i, 1, Length[roots]}];

This means you would have to tell me what Table, Join, Length etc. mean.

That's all for now. Thanks for you help.

Tushar Saxena
saxena@cs.albany.edu
From: aaronm.bbs@cybernet.cse.fau.edu
Newsgroups: sci.math.symbolic
Subject: Mma Fourier accuracy
Date: 30 Jul 92 18:01:52 GMT
Organization: Florida Atlantic University, Boca Raton

I've been using the Fourier[] command to find the discrete 
Fourier transform of a list. When I 
ListPlot[Abs[Fourrier[...]]] as in the book I sometimes get
strange points scattered arround, even negative ones.
This happens with 256 sample points (as in the example in the book)
but 64 does not give this problem. I am using 2.0 for DOS
Does anyone have experience with this problem? please post 
or mail to MEYEROWI@acc.fau.edu. Thanks!
From: cfw2@po.CWRU.Edu (Charles F. Wells)
Newsgroups: sci.math.symbolic
Subject: A Problem with Reinstalling Mathematica for Windows
Date: 27 Jul 92 14:39:01 GMT
Organization: Case Western Reserve University, Cleveland, Ohio, (USA)


I run Mathematica for Windows on a Gateway 486-33 machine with

an ATI Graphics Ultra Video board.  Today, I experimented with

going into 800 x 600 video mode instead of the usal 640 x 480. 

I then used the Defaults window in Mma to enlarge the input and

output files.  This did not take effect in the Newnb-1 window,

so I exited Mma and tried to restart it.  It froze at 11%.  I

tried many things, including turning the machine off and on and

changing back to 640 x 480 mode.  The same thing always

happened.  So I reinstalled Mathematica.  It worked now, but the

Defaults window was in a horrible mess.  It showed part of the

font commands that the notebook normally does not show.



I suspected that the installation process had inserted a new

defaults.ma file but had left an incompatible defaults.mb file

on the disk.  So I renamed the defaults.mb file and reloaded

defaults checking the no  binary option.  Now everything works

fine.  



I don't know what caused the problem originally, but I thought

others would want to know about this problem that reinstallation

can cause.





Charles Wells

Department of Mathematics

Case Western Reserve University

10900 Euclid Avenue

Cleveland, OH 44106-7058

216-368-2893
Newsgroups: sci.math.symbolic
From: kir@dsd1.nyser.net (Harald Kirsch)
Subject: sigma-algebras and probability spaces
Organization: Institut fuer Informations- und Datenverarbeitung
Date: Mon, 27 Jul 1992 07:48:30 GMT



Dear Netters,

I am looking for a sw package that can do symbolic computations in
$\sigma-$algebras (set theory). In the moment I have access only to
Maple and it looks like it can not do what I need:

I simply want to tell the sw that e.g. A and B are sets and that they
are disjoint without saying s.th. about the contents of A and B. Then
the SW should be able to derive that e.g. the following holds:
     $A \subset   A\cup B$
     $A \setminus B = \emptyset$
     $A \subset \C{B}$ (where \C{B} denotes the complement of B
                        relative to a set which contains A and B as
                        subsets.)
     etc.

In the next step I need to do symbolic math with probabilities. To
continue the example above, I tell the computer the probabilities
P(A) and P(B) and it should be able to derive that 
    $P(A\cup B) = P(A)+P(B)$  (because $A\cap B=\emptyset$)
    (etc. with more A's and B's and more known probability values)

Does anybody out there know about a sw package able to solve those
problems. If not, it would also help to get some pointers to
literature with algorithms dealing with symbolic computation in
$\sigma-$algebras and probability spaces. (No pointers to Bayesian
Networks please, I know them already.) 

Please send your answers to  kir@iitb.fhg.de

Thanks in advance,
  Harald Kirsch

Newsgroups: sci.math.symbolic
From: orourke@sophia.smith.edu (Joseph O'Rourke)
Subject: Re: Finding convex  hull ?
Organization: Smith College, Northampton, MA, US
Date: Thu, 23 Jul 1992 11:56:09 GMT

In article <PHR.92Jul22170347@soda.berkeley.edu> phr@soda.berkeley.edu (Paul Rubin) writes:
>The best known algorithms for convex hull are very complicated.[...]
>I believe "Compuational Geometry" by Preparata and Shamos has some
>info on convex hull algorithms.

	Yes.  Graham's algorithm does not generalize to d > 2.  There
are several algorithms that do generalize, however.  One is gift-wrapping.
Another is beneath-beyond.  Both are described in P&S.  Edelsbrunner's
book has a detailed description of beneath-beyond that is close to
code.  The worstcase size of the hull of n points in d dimensions is
n^{[d/2]} (that's floor of d/2), and the beneath-beyond algorithm
nearly achieves that complexity.
Newsgroups: sci.math.symbolic
From: chepan@gsusgi1.gsu.edu (Parthasarathy Nambi)
Subject: Integration of coupled differential equation
Summary: Integration of coupled differential equations
Keywords: integration, differential equations
Organization: Georgia State University
Date: Wed, 22 Jul 1992 19:08:28 GMT

 Hi I need help with Mathematica.

 I have a research problem that requires solving a set of
 coupled differential equations (one is second order and the other
 fifth order).  The source of my differential equations is a paper:

 R.W. O'Brien and L.R.White, Journal of Chemical Society
 Faraday Transactions, 2, vol 74, 1607 (1978)

 In this paper the authors state: " the 5th order scheme of Nordsieck for
 the integration of coupled differential equations was used". Does anyone
 know how to implement Nordsieck method using Mathematica?

 I am aware of the fact that coupled differential equations can be
 solved using Mathematica - as given in S.Wolfram's book. But these
 are simpler than what I have to deal with.

 If there is anyone out there who has solved complicated coupled
 differential equations using Mathematica please send e-mail to
 chepan@gsusgi1.gsu.edu.

 I am using Mathematica on a Iris Indigo with 16 MB memory.

 Any other info related to this will also be appreciated.

 P.Nambi

Newsgroups: sci.math.symbolic
From: ppc1@cec1.wustl.edu (Peter Pui Tak Chiu)
Subject: simplification
Organization: Washington University, St. Louis Mo.
Date: Sat, 25 Jul 1992 11:57:33 GMT


hi everyone,

i have a real naive question:

        how to do symbolic simplification using scheme, lisp or anything...?

what i mean is symbolic simplification like MATHEMATICA.

here are some examples:

          (* a (+ b (/ c a))) ==> (+ (* a b) c)
          (+ (* a b) (* a c)) ==> (* a (+ b c))

these are just very simple cases and are intended to explain what i mean...
i want to know a way to find the "simplest form" of any algebric expression.
not only those which are as simple as the above.

can anyone tell me how to do it or refer me to some books that talk about it?

thanks in advance

peter

Newsgroups: sci.math.symbolic
From: richard j. gaylord <gaylord@ux1.cso.uiuc.edu>
Subject: Re: Mathematic Maual or Help on some functions
X-Useragent: Nuntius v1.1
Organization: university of illinois
Date: Sat, 25 Jul 1992 08:34:58 GMT

Mathematic Maual or Help on some functions

the mathematica manual you want is  called "Mathematica: A System For
Doing Mathematics by Computer" which is a book sold, separately from the
software in bookstores or available in the free domain source known as
the library.
Newsgroups: sci.math.symbolic
From: nikhil@enuxha.eas.asu.edu (Venkatesh Nikhil)
Subject: simultaneous equations.
Organization: Arizona State University, Tempe, AZ
Date: Mon, 27 Jul 1992 20:02:13 GMT


mathgroup,
	  I need your help on the following problem.I have 8 equations as
follows:
a=P*mcp*ac*tc*tf*tr
b=P*mcp*(4*ac*tc*tf+ac*tc*tr+2*af*tc*tr-ac*tf*tr+ac*l*tc*tf*tr)
c=P*mcp*(4*ac*tc+4*af*tc+l*4*ac*tc*tf+l*ac*tc*tr+2*l*af*tc*tr-l*ac*tf*tr)
d=.....
"
"
"
h=..............

I need to solve these equations simultaneously for "ac" in terms of a,b,c,d,
e,f,g & h. So, here i need to eliminate the other variables like P, mcp, tc,
tf, tr, l, L, af, etc. 
I am using mathematica and tried the commands eliminate (but my PC ran out
of memory before giving me the solution) and Solve[eq,var,elim] ( but this one
did not work too).
Have any of you encountered a similar problem? Is there a way to obtain "ac" in
terms of just a, b, c, d, e, f, g&h eliminating the rest. I would appreciate
your suggestions. Is there any other software package i could use for this
problem?
Here is thanking you in advance.
 								Sincerely,
								Nikhil...

--
*******************************************************************************
	NIKHIL VENKATESH  		(602)-929 0927  
Summer in Arizona, wow!!! U really should be here. I'm not sarcastic!!!!!!
*******************************************************************************
From: rclc6@rw8.urc.tue.nl (Arjeh Tal)
Newsgroups: sci.math.symbolic
Subject: Interfacing numerical/graphical software
Summary: Combining the power of traditional numerical/graphical librarys with CA systems
Keywords: CA, maple, numerical, graphical, NAG, AVS, AXIOM
Date: 28 Jul 92 13:13:53 GMT
Reply-To: rclc6@urc.tue.nl

I would like to review the interface problematic of CA systems with numerical
and graphical applications. 
  Examples:
- Maple's evalhf is much slower than traditional compiled programs.
- Maple and AVS.
- CA systems (transparant?) interaction with other programs etc.
- Athena project: NAG and REDUCE? (AXIOM and NAG).

Any contribution is welcome.

-- 
e-mail: rclc6@urc.tue.nl                | Arieh Tal
phone:  +31 (0)40 474240                | Eindhoven University  of Technology
fax:    +31 (0)40 447035                | P.O. Box 513, 5600 MB Eindhoven, NL

Newsgroups: sci.math.symbolic
From: pap@air12.larc.nasa.gov (Peter A. Padilla)
Subject: PARI port to DOS?
Keywords: PARI
Reply-To: pap@air12.larc.nasa.gov (Peter A. Padilla)
Organization: NASA/SVMB
Date: Thu, 30 Jul 1992 15:24:48 GMT

Can anyone tell me if PARI has been ported to DOS machines (386 or 486) and if
so, where can I get it. Please email me. Thanks in advance.

Peter A. Padilla
pap@air12.larc.nasa.gov
From: gaylord@UX1.CSO.UIUC.EDU
Newsgroups: sci.math.symbolic
Subject: computer simulation of the development of the universe
Date: 28 Jul 92 15:05:16 GMT

A functional programming approach to cosmological simulation:

A general model of the chronology of the Universe

history = FixedPointList[(..#..)&, initialconfiguration] 

the anonymous function (..#..)& is supplied by the reader: 

special cases:
1) theist: anonymous function = GOD
2) pantheist: initialconfiguration = GOD

included: the many-worlds interpretation of quantum mechanics
not included: quantum fluctuations (?)

sorry, about that. too much time spent hacking recently, i guess.  

richard j. gaylord, university of illinois, gaylord@ux1.cso.uiuc.edu

"if you're not programming functionally, then you must be programming
dysfunctionally"
From: gjc@mitech.com (George J. Carrette)
Newsgroups: sci.math.symbolic
Subject: Re: Symbolic Algebra subroutine library?
Date: 27 Jul 92 09:40:31 GMT
Organization: Mitech Corporation, Concord MA

In article <1992Jul24.224350.12931@cco.caltech.edu>, terry@wag.caltech.edu (Terry R. Coley) writes:
> I would like to know if there is a symbolic algebra subroutine 
> library suitable for linking to C/C++ programs.  More specifically,
> I would like to use the algebraic manipulation capabilities of a
> package like Mathematica (as just one example) available from
> within a compiled and linked program.  

I think your best bet is to look at the SCM scheme interpreter
(written in C) and the algebra system that runs in it. 

Then, your API to the system is going to be
a C subroutine to cause the initialization of the Scheme interpreter,
and then pretty much from that point on you will be calling
some kind of one-shot EVAL subroutine from C. Of course you will have
to call "cons" and "intern" or at least "read-from-string" in order
to create the expressions you want to evaluate.

  (algebraic-simplify '(+ a a))


-gjc
From: jcbhrb@nic.cerf.net (Jacob Hirbawi)
Newsgroups: sci.math.symbolic
Subject: Re: New class of functions found, impact of CAS on math
Date: 21 Jul 92 22:53:34 GMT
Organization: CERFnet

In his post to sci.math.symbolic <1992Jul21.204630.2957@nntpd.lkg.dec.com>
Nasser Abbasi <abbasi@star.enet.dec.com> writes:

> there is an interesting article about how using computer algebra
> systems (MAPLE), it helped in finding a new class of function, called
> terminal summations.
> look it up, it is on page 35 of July 20,1992 Electronics Engineering
> Times magazine.
> it is too long to type, so here are some psudo-random quotes from the
> article :(printed with no permission)

[ several extracts from the article deleted ]

Very interesting article! I'm not sure I beleive his claim: "I've shown that
problems of divergence can be banished from math applications"; but the
example about the "companion" function to exp(x) is worth a closer look.
You have to admit that you don't expect this function to converge quickly
(if at all):

      B(x) = 1 + x + 2!x^2 + 3!x^3 + 4!x^4 + ... + n!x^n + ...
  
So does anyone know more about this "Terminal Summations" stuff ?

Jacob Hirbawi
JcbHrb@CERF.net
From: whitmore@iastate.edu (Kurt D Whitmore)
Newsgroups: sci.math.symbolic
Subject: Fonts in Mma graphics (Macintosh)
Date: 22 Jul 92 16:35:34 GMT
Organization: Iowa State University, Ames IA

Problem:
________
I'm trying to get a font in a Mma graph other than courier.


A System for Doing Mathematics by Computer {ASDMC} (Page 468) says:
________________________________________________________

	DefaultFont -> font

Example:
________

	Show[%,DefualtFont->{"Times-Italic",6}]


		This doesn't work nor does replacing Times-Italic with:
			TimesRom
			NewCenSchRom	[Acutual Printer Fonts]
				.
				.
				.
			et cetera

		Though changing the size does work.
		
		Also on the screen, the font does alter but doesn't
		affect the print out, it is still courier.

	I looked at the PostScript code and the correct font information
	is their.
	
			... MathPictureStart
			    /Times findfont 12 scalefont set font ...

Thanks,



Kurt D. Whitmore
whitmore@iastate.edu

		
Newsgroups: sci.math.symbolic
From: steve@osc.edu (Steve Koehl)
Subject: symbolic algebra
Keywords: symbolic algebra mac
Organization: Advanced Computing Center for Arts and Design
X-Newsreader: Tin 1.1 PL4
Date: Thu, 23 Jul 1992 17:25:22 GMT

I'm looking for a low power symbolic algebra package 
with a very intuitive UI for the Mac.  We at OSC are 
having a class of high-schoolers and one of the "non-
numeric" things we want to show is computer algebra.  
Oh, yes, I'm looking for something that is free, and 
down-loadable from the internet.  Thanks ** 2
From: whitmore@iastate.edu (Kurt D Whitmore)
Subject: Re: Symbolic Algebra subroutine library?
Organization: Iowa State University, Ames IA
Date: Sat, 25 Jul 1992 16:19:54 GMT

In <1992Jul24.224350.12931@cco.caltech.edu> terry@wag.caltech.edu (Terry R. Coley) writes:
 

>I would like to know if there is a symbolic algebra subroutine 
>library suitable for linking to C/C++ programs.  More specifically,
>I would like to use the algebraic manipulation capabilities of a
>package like Mathematica (as just one example) available from
>within a compiled and linked program.  For example, the program
>might construct an expression like (a + b)(c + d) represented
>internally in some data structure (maybe a tree, maybe just a 
>string).  Then, a subroutine called with this expression as an
>argument would perform an operation on the expression and return
>the result in the same data structure type.  For example, a routine
>called multiply might return ac + ad + bc + bd in the data structure.

>After watching this news group for a few weeks, it appears most
>symbolic work is done through front ends like that with Mathematica
>or Maple.  Do either of these have an API (application programmer
>interface) for accessing their functionality?

>Some people have suggested shelling out a separate process to
>run Mathematica and then parse the resulting output.  This is
>not acceptable for a variety of reasons, not the least of which
>are speed, portability, etc.  My program will be generating
>hundreds of expressions, doing simplifications, and using the
>results.  For now I have programmed the simple expression tree
>simplifications myself, including some simple derivatives.  But
>as the expressions the program creates become more complex, I
>will not be able to compete/reproduce the functionality of
>good symbolic algebra packages.  Therefore, I would like an API
>to such a package!  Any suggestions?

>-- 
>	- Terry
>terry@wag.caltech.edu 818-397-2724 818-585-0918 (FAX)
>Terry Coley, Caltech 139-74, Pasadena, CA  91125


Mathematica 2.1.x.x has totaly reworked Mathlink and has improved the documentation greatly.

MathLink allows C functions to be defined externally to mathematica, much like
what you want to do, and then used as functions within Mma via Mathlink.

Not only can you have Mma call up C functions but you can also have C call up Mma to do calculations and pipe it back to your C program if you dont want to
write code for say, a nasty integration.

Kurt D. Whitmore
whitmore@iastate.edu

Newsgroups: sci.math.symbolic