                                            Version: 0.84 (English)
                                            for Windows 98
                                            released: 6 / 14 / 2002
                                            This version is freeware
                                            
       Have you got the documentation package, too ?

  If you obtained this file from a shareware distributor's 
  site, you may have missed the documentation. It is contained 
  in a separate file, available from my homepage at:
  http://members.aol.com/rf21exe/
  (please click on the download icon).
  
  Once on my site, be sure to get "dll.zip" as well, it contains two 
  DLLs you might need to run the printer utility "rfprint.exe".


                        Welcome to RF21 !

Thank you for trying RF21.EXE. You are looking at a mathematics 
application with a completely new concept. The focus is on 
numeric calculation of all kinds of functions, single valued, 
multivalued, familiar ones, strange ones, and functions too 
complicated for any pocket calculator. Whatever isn't installed 
here can be created by you, the user.
The main areas of service offered are the following :

 - an environment called the "revolver", designed for comparing 
   and investigating the behaviour of functions.
 - extensive support for installing user defined functions of
   various kinds and building libraries. User function database.
 - numeric features such as numeric integration and
   derivation, search for zeroes etc., nonlinear function
   minimizer, nonlinear solver, accelerated summation of series.
 - two plotting devices: one for creating instant screenplots,
   the other for designing printable plots based on those 
   screenplots
 - within limitations, RF21 lends itself to mathematical
   programming. Applications to a number of problems have been 
   installed by the author. 

RF21 is unrestricted freeware. By trying this version 0.84 and 
e-mailing your comments, or contributing libraries, you are 
supporting further development of this program. If you are a 
mathematics developer yourself, you can take advantage of the 
source code as a platform on which to build your own 
applications.

Some areas not covered by RF21 (such as eigenvalues and -vectors 
of large matrices, polynomials and their roots, power series 
arithmetics) are extensively covered by my other program MA.EXE, 
which is shareware and available for download from that same 
RF21-homepage.


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HOW TO GET STARTED
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This distribution (and all future ones) contains the files 
README.TXT (which you are reading) and INSTALL.TXT containing all 
technical and installation related information. This is the only 
documentation you'll ever find in the executable package. 
The user documentation files are wrapped separately. 
  The documentation package proper is available for download 
from my homepage:
 
             http://members.aol.com/rf21exe 

It will be updated independently (check the release date) and 
carries the same version number as the executable that is being 
documented.
Keep checking my homepage to see what else (libraries etc.) might 
be available in other packages. There is one library available now
specializing in multi dimensional numeric integration.


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ABOUT THIS VERSION 0.84
-----------------------------------------------------------------

Since version 0.78, which was the first release, small-bug-removal
is under way (with the help of users submitting bug reports), while 
new mathematical features are being added. Ultimately, I'm heading
for a version 1.0  that should meet the taste and expectations of 
broader audiences as well as mathematical freaks.

Version 0.82 is the first ever released native Windows version, it
was tested under Windows98 and should run on all 32 bit Windows
systems. It feels and is operated much like the DOS program it once
was. I'm in no hurry to restructure the user interface and adapt it
to Windows style - it would create a lot of work for myself, bring 
nothing in terms of functionality, confuse users, and make a future
porting to Linux much harder. Besides, I'm not convinced of the
superiority of graphical interfaces, except when dealing with issues
that are of a graphic nature, such as plots. 

Recently added features:
Version 0.82 brings the fraction recognizer, it recognizes fractions 
and also some quadratic irrationals from their decimal form.

Version 0.84:
- The summation menu for computing finite and infinite sums (=series)
over the current revolver formula. It has a built-in assistant for
installing parameter dependent infinite sums as user functions. Also,
there is an integrated convergence acceleration algorithm to create
instant results on slowly convergent series.
- Next to the function class for infinite series, another new function
class has been added. Containing an open number of formulae, it is
equivalent to an if...else if cascade in conventional programming.
Programming conditions with more than 2 branches thus becomes a lot 
easier.
- Version 0.84 does away with some annoying restrictions of the past.
In user functions, assignment to arguments is now OK. Uppercase charac-
ters are allowed as revolver arguments, too, and also as #static
and #const variables. They are now of even status with lowercase charac-
ters in all aspects.
- The calculation notepad supports the <F10> key to paste the previous
line back to the input.
- There is a new predefined function "domaincheck()".


The final user interface will have to wait until version 1.0. In the
meantime, I'm adding and testing mathematical features. The outcome 
of these tests will have an impact on the final design. 

Thank you for beta-testing this version and sending your comments 
and bug reports. They are important guidance to me in deciding on the 
final design. 


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ABOUT THE LIBRARIES
---------------------------------------------------------------------

The library files (as listed below) are meant to assist the 
documentation. They are not necessary for proper functioning of 
the program, but the documentation files rely on them, so be sure 
to have them in your work directory. 
The libraries carry comments both in English and German. They 
contain examples going beyond the scope of the user documentation.
Some are meant as actual applications, others just as a source of 
inspiration. They are neither optimized nor foolproof.
Discard what you don't need, after checking if the object isn't a
component of some other application you intend to keep (use the 
callfinder feature of the user function database to find out).


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IN CASE OF TROUBLE
---------------------------------------------------------------------

If anything doesn't work as promised, why don't you send me an e-mail
to rf21exe@aol.com. Be as detailed as you can about the problem, and 
I'll be happy to give as much assistance as is possible by e-mail or 
by phone. Your computer may behave different than mine and I cannot 
foresee every possible reaction, until it is brought to my attention.

In case of satisfaction or dissatisfaction, I'd still like to have
your comments:

  - Is the program of any use for your work ?  
  - What is good, what is awkward ?
  - What features would you like to see added ?
  - Was it easy to get started ?
    Is the documentation sufficient and understandable ?
  - What country are you from ?
  - What is your profession ?   


--------------------------------------------------------------------
LIST OF FILES IN THIS PACKAGE
--------------------------------------------------------------------

    file            bytes   contents
    ----------------------------------------------------------
    README.TXT              this file
    INSTALL.TXT             Installation notes
    FILE_ID.DIZ             for redistributors only
    PAD_FILE.XML            for redistributors only
        
    RF21.EXE        983146  main executable file
    RFPRINT.EXE     393216  printer interface application

    RF21.DAT        1017         
 
    
                            LIBRARIES...
                            
    ASTRO.LIB       12684   astronomy
    COMPLEX.LIB     11973   complex numbers, the Cardano formulae
    CONFRAC.LIB	    17200   on continued fraction expansions
    CONVERT.LIB     3815    unit conversions
    DESKTOP.LIB     659     
    DIOPHANT.LIB    25156   integer utilities
    EBENGEO.LIB     3978    applications to plane geometry
    FUNCTION.LIB    14360   functions
    FUNNY.LIB       12531   functions to plot
    GEO.LIB         7403    about Earth     
    KEPLER.LIB      7222    Keplerian orbits
    LINALG.LIB      8094    planes and lines
    MATRIX.LIB      6861    eigenvalues, char. polynomial        
    NUMTHEO.LIB     9116    integer utilities, continued fraction expansions
    PARTIT.LIB      7494    self invoking functions, different kinds of 
                            partition numbers, various ways to compute them
    PHYSIK.LIB      7496    physical constants
    POLYEDER.LIB    7555    formulae for simplices
    RANDOM.LIB      8400    random numbers and -vectors
    SCHNABEL.LIB    7174    demo examples for solver and minimizer
    SERIES.LIB      1822    infinite series as user functions
    STEREO.LIB      8754    problems in 3 dimensions
    STOCH.LIB       32491   stochastics
    UTILS.LIB       24937   mixed utilities

Please look for all other files in the documentation package.


Copyright:
Christoph Hohmann, Kalk-Muehlheimer Str. 36, 51103 Cologne, Germany 

e-mail to:
rf21exe@aol.com  
