FUNEX.TXT
                     Function Experimenter
                     Version 1.16, US 1994


INTRODUCTION:
FUNCTION EXPERIMENTER is a program that can draw a curve of 
any mathematical function of the form  y = f(x).  The program
can also be used as a calculator and to solve equations with
one or two unknowns.  

The program is especially designed for teaching purposes, but 
can also be used for other purposes.

FUNCTION EXPERIMENTER is so simple and user friendly that most 
pupils can use it with a minimum of instruction.  Everywhere
in the program are Help facilities that tell the user what to 
do.  Error messages are instructive and easy to understand.  


SYSTEM REQUIREMENTS:
This program requires Microsoft Windows version 3.0 or later.  
VGA color monitor and mouse recommended.
Math coprocessor supported but not required. The program is 
quite fast even without a math coprocessor.  


INSTALLATION:
There are no special considerations to take when installing 
this program.  It is recommended that you make a directory 
named C:\FUNEX  on your hard disk and copy all files from the 
program diskette or zip file to this directory.  Use File 
Manager to do this.  

You probably want your Program Manager to have an icon for 
FUNCTION EXPERIMENTER.  Select "New... " in the "File" menu of 
the Program Manager to make a new program item.  The command 
line is FUNEX and the working directory is C:\FUNEX 
If you are in doubt, read the Windows manual.  An alternative 
way to put the new icon into the Program Manager is to drag 
FUNEX.EXE with the mouse from File Manager into the appropriate 
group in Program Manager.  This requires that both the File 
Manager and Program Manager are visible at the same time.  

(It is also possible to start the program from DOS by writing 
WIN C:\FUNEX\FUNEX ) 



TO THE TEACHER:
The basic pedagogical idea behind the program is that it en-
courages the pupil to experiment in a creative and intelligent
way.  If the pupil wants to know what happens when the formula
is changed in a certain way, he or she can get the answer 
right away.  A clever experiment is rewarded immediately with 
an interesting curve.  

The program can handle virtually any mathematical expression.  
No matter how fanciful an equation the pupil comes up with,
the program will always give a correct answer.  All standard 
mathematical functions are recognized, and the program is 
tolerant to different ways of writing.  

How to make a curve:
The program has two long writing fields where you can write 
one or more equations with y on the left side of an equal sign 
and any expression containing x on the right side of the equal 
sign.  Simply press Enter to see the curve whenever you have 
written an equation.  

It is recommended to let the pupils start with one of the
examples that are stored in advance.  This is done simply by 
clicking with the mouse on one of the buttons on the screen.  
This gives the pupils an example on how to write an equation,
and thereby saving a lot of explanations.  

The pupils can now make changes in the equation they have got.  
They can start with changing the coefficients and see how this 
affects the shape of the curve.  Later they can change a 
polynomial of second degree to one of a higher degree.
They can swap x and y to see the curve get mirrored in the x=y 
line.  Or you can leave it all to the pupils' fantasies to 
invent new functions.  

It is a good idea to make some buttons in advance with 
examples of the equations you want the pupils to work with.  
You can define a maximum of eight buttons.  This is how to 
make your own buttons:  First write the equation and make sure 
the curve is as you want it.  It is recommended to use letters 
as coefficients and define the values of these on the second 
line.  This makes it easier to change the coefficients.  Write 
the equation neatly with spaces between the signs.  You may 
adjust the limits of the coordinate system with the menu point 
"Axes".  Use the same coordinate system for all equations.  
Now you can make a button for your equation by choosing the 
menu "Define" and "Buttons".  

When you are finished making buttons, save these as a setup 
file.  Choose the menu "File" and "Save setup".  The setup 
will be saved in a file with the name you choose.  Choose the 
name STANDARD if you want the new setup to be loaded auto-
matically next time the program is started.  If you choose 
another name, then the pupil has to retrieve the setup by 
using the menu "File" and "Read setup".  

How to copy a setup from one PC to another:
The setup files all have the extension FUN added to their 
names, and are stored in the directory C:\FUNEX.  You can copy 
these files via a diskette to all the computers in the 
classroom.  You may use the File Manager to copy files.  

How to prevent the pupils from changing the setup:
You can prevent the standard setup file STANDARD.FUN or any 
other setup file from being changed by giving it the "Read 
Only" attribute.  Open File Manager; pick the file you want to 
protect; choose the menu "File" and "Properties"; and check 
the "Read Only" attribute.  Obviously, you have to remove the 
"Read Only" attribute again when you later want to change the 
setup.

How to change the font:
If you aren't satisfied with the style of the characters in the
writing fields then you may change it.  Use the program NOTEPAD
to edit the file STANDARD.FUN.  Write the name of the character
font you want in the second line between the quotation marks,
for example "Arial", "MS Sans Serif", or "Fixedsys".  Loading 
the font may take a few seconds the first time you write an
equation.

If you are in doubt about how to use FUNCTION EXPERIMENTER,
then use the help facilities.  There are Help buttons every-
where in the program telling you what to do.



INTERNATIONAL USE:
To define comma or point as decimals separator use the menu 
"Define" and "Decimals".  

You can use "*", "", or "" as multiplication sign.  The 
asterisk "*" is recommended because it is readily available on 
the keyboard and is commonly used as multiplication sign in 
other computer programs.  The dot "" and cross "" are 
allowed in order to support official standards.  However, 
there is a risk that the dot will be confused with a point, 
and the cross will inevitably be confused with the letter X!  
You can use "/", ":", or "" as division sign.  The american 
division sign "" should not be used in countries where this 
sign can be interpreted as a minus.

A caret "^" is used as a sign for "raise to the power of".  
Using superscripts for this purpose, as is common standard 
outside the computer world, is not supported here because such 
an expression would be very complicated to write and difficult 
to read, especially if the exponent is a compound expression.  

If the abovementioned signs are not found on your keyboard, they
may be written in the following way in FUNCTION EXPERIMENTER: 
Multiplication dot ""  =  Alt+.
Multiplication cross ""  =  Alt+x
American division sign ""  =  Alt+/
Caret "^"  =  Shift+6  or  Alt+UpArrow

National letters like , , , , etc. are allowed as symbols.
The program does not distinguish between upper and lower case.

Special versions of Function Experimenter in languages other
than English can be developed on request.



USER FEEDBACK:
Suggestions for improvement of this program from the users 
will be appreciated, and the most useful suggestions will
be rewarded with a free update.

If the program doesn't behave as expected, if the wording of 
help and error messages could be more clear, or if certain 
features are missing, then please write to the address below 
(no later than 1996).  Please state whether you are using the
program for teaching or for other purposes.  You may include 
authentic unedited log-files showing the pupils' reactions.

Please acknowledge that the basic concept of FUNCTION 
EXPERIMENTER is a program that is so logical and simple that a 
schoolkid can use it without instructions.  I am not going to 
make 3-D drawing, import and export of data files, and other 
complicated features conflicting with this concept.  There are 
other programs such as spreadsheets, math packages, and 
presentation programs to support such needs.




SPECIFICATIONS:
Internal accuracy:     Approx. 15 significant digits.

Numbers range:         Real numbers from  10^(-308) to  10^308,
                       and 0.  

Arithmetic operations: Addition, subtraction, multiplication, 
                       division, raising to power.  Standard 
                       hierarchy of operators.

Mathematic functions:  Square root, round, magnitude, common 
                       and natural logarithms and exponential 
                       functions, trigonometric functions,
                       inverse trigonometric functions, hyper-
                       bolic functions, etc.  All functions 
                       can be combined to expressions of 
                       virtually unlimited complexity.  

Results format:        Fixed number of decimals or floating 
                       point with specified number of signifi-
                       cant digits.  
                       Choice of point or comma as decimals 
                       separator.
                       Exponential notation.
                       0/0, 0^0, imaginary and complex results 
                       indicated as "not defined".
                       Division by 0 and overflow indicated as 
                       "infinity", or "- infinity".

Graphic resolution:    Depends on screen type.
                       Every curve is drawn on basis of 
                       approx. 160 calculated points.  

Number of curves:      Up to approx. 40 simultaneous curves in 
                       9 colors.  

Printout:              Printout of curve and equation on any 
                       printer or plotter supported by 
                       Windows. (Only version 2 of Function 
                       Experimenter).

Export:                Export of curves via clipboard, .WMF
                       file or .BMP file.  Export of numeric
                       results via clipboard.



ORDERING INFORMATION:

Version 1 of FUNCTION EXPERIMENTER is shareware and may be 
copied freely.  Registered users will receive version 2 or 
later which has added facilities for printing curves.  The 
registration fee is 50 US $ for single users and 200 $ for 
institutions, or equivalent amounts in other currencies.  

Methods of payment:

- International checks.

- Cash (registered mail).

- Bank transfer to GiroBank Denmark, Swift code GICODKKK, 
  Account No. 114 0817.

- Europe: Giro transfer to Denmark 114 0817.

No credit cards, please.


          ACON ApS Software
          P.O. Box 843
          2400 Copenhagen NV
          DENMARK
