GraphApplet 1.0

GraphApplet 1.0

Author Patrik Lundin, plundin@kagi.com, http://www.javathings.com

Description
How To Setup The Applet
All Functions
Parameters
Known Issues
License

Description

The GraphApplet 1.0 is a full featured Graphing Calculator with some rare features added.

It is recommended that you use Netscape 4.x or higher or IE 4.x or higher for this applet and
at least 800x600 resolution with more than 256 colors. Result in older browsers and with different
resolution or color depth may vary, some problems have been noticed in older browsers.

The GraphApplet has all the common operators and functions as expected from any scientific
calculator and combines it with function graphing capabilities.

The GraphApplet supports juxtaposition which means you can write your expressions just as you
would write them on a piece of paper, for example xcos(x) or 5x^3-6x

The GraphApplet has support for symbolic differentiation using the diff function.

To use the applet as a calculator click on the buttons or use the keyboard to form your expression
and then press enter or click the Eval button to evaluate.
Note that when you click on a function button it will fill in a left parenthesis, you will have to match it
with a right parenthesis either by clicking on the ) button or enter it with the keyboard.

To draw a function enter the function by clicking on the buttons or enter them with the keyboard
and then press the PlotF button, you can only draw function of type y=f(x) .
To zoom into an area, select an area with the mouse ( click, hold down and drag ) and release,
the area you selected will be zoomed in, to zoom out use the ZOut button.
To reset the bounds to the original x:[-10,10] y:[-10,10] click on the Reset button.

To clear the input field click the Clear button, to clear a individual drawed function double click on the
function name in the list to the right of the applet or click on the Cls button to clear the whole screen.

To enter something into memory first click the M-> button and click on either m1 or m2,
to clear the memory first click on MCls and then either m1 or m2

How To Setup The Applet

Follow these steps to setup the applet on your webpage:

1. Copy the zip-file called gapplet.zip to your web folder.
If you are using ftp make sure the zip-file is uploaded as binary and not ascii.

2. Copy this applet html tag to the page where you want to use the applet :

<applet archive="gapplet.zip" code="GraphApplet.class" width=655 height=360>
</applet>

If you have an old browser that doesn't support the use of the archive attribute in the applet tag
then you will have to extract the zip-file maintaining the file structure to your web folder.

The only browser today still in use that do not support the archive tag is IE 3.0,
all newer 4.x browsers and Netscape 3.0 supports the archive attribute.

Please note that is recommended to use a newer browser for this applet ( IE and Netscape, version 4.x or higher )

3. Open the page in a webbrowser that supports Java and start to use the GraphApplet.
The GraphApplet is best viewed in at least 800x600 resolution and more than 256 colors.

All Functions

Calculator Controls

Eval - Evaluates an expression, the calculator first tries to evaluate the expression,
if it fails then it tries to draw the expression.

Clear - Clears the input area.

PlotF - Plots a function of type y=f(x)

ZOut - Zooms out the current area with a factor of x2.
To Zoom into an area, select the area with the mouse and release.

Reset - Reset the bounds to the original x:[-10,10] y:[-10,10]

Cls - Clears the whole drawing area and all functions.
To clear an individual function double click on the function in the list to the right of the applet.

M-> - Enters an expression or a value into memory, first click this button and then chose either m1 or m2

MCls - Clears the memory, first click this button and then on either m1 or m2 to clear that memory.
Note that memory will be gone if you leave the page with the applet and then return at a later point.

m1 - Memory 1

m2 - Memory 2

Operators and Functions

sqrt - sqrt of a value or expression.

sin - sin of a value or expression.

cos - cos of a value or expression.

tan - tan of a value or expression.

atan - atan of a value or expression.

acos - acos of a value or expression.

asin - asin of a value or expression.

acotan - acotan of a value or expression.

exp - The constant euler raised to a value or expression.

ln - The natural logarithm.

10log - The 10 logarithm of a value or expression.

fac - The faculty of a value or expression.

diff - Symbolically differentiates an expression of one variable

pi - The constant PI

euler - The Euler constant, base for the natural logarithm.

+ - Addition operator.

- - Subtraction operator.

* - Multiplication operator.

/ - Division operator.

^ - Raised to operator.

The calculator also supports the following functions when entered through the keyboard:

sinh - Hyperbolic sine

cosh - Hyperbolic cosine

tanh - Hyperbolic tangens

abs - Absolute value of value or expression.

ceil         - Returns the smallest (closest to negative infinity)
                 value that is not less than the argument and is equal to
                 a mathematical integer.

floor       - Returns the largest (closest to positive infinity)
                value that is not greater than the argument and is
                equal to a mathematical integer.

sfac - Semifaculty of value or expression.

round - rounds the argument to the closest mathematical integer.
Example: round( 3.4 ) = 3.0, round( 4.99 ) = 5.0 etc...

fpart - returns the decimalvalue of its argument

[base]log(..) - any logaritm. Example: 10log(10) = 1.0, exp(1)log(exp(1)) = 1.0

% - Modulo.

== - Equal, returns 1.0 if it's arguments are equal or 0.0 othervise.

!= - Not Equal, returns 1.0 if it's arguments are not equal or 0.0 othervise.

&& - And, returns 1.0 if both arguments evaluates to 1.0, or 0.0 othervise.

|| - Or, returns 1.0 if any of it's arguments evaluates to 1.0, or 0.0 othervise.

> - Larger than, returns 1.0 if the value of the argument to the left is larger
than the value of the argument to the right, or 0.0 othervise.

< - Less than, returns 1.0 if the value of the argument to the left is less
than the value of the argument to the right, or 0.0 othervise.

>= - Larger than or equal to, returns 1.0 if the value of the argument to the left is larger
than or equal to the value of the argument to the right, or 0.0 othervise.

<= - Less than or equal to, returns 1.0 if the value of the argument to the left is less
than or equal to the value of the argument to the right, or 0.0 othervise.

! - Not, returns 0.0 if it's argument evaluates to 1.0 and returns 1.0 if
it's argument evaluates to anything other than 1.0

Parameters

All the applets colors and even the layout can be controlled with parameters to the applet.
A parameter is given by inserting a <param> tag in between the opening <applet> and
closing </applet> tags.

Example:

The name part of the parameter is one of the names described below and the value
is the value you specify for the parameter.

Color Parameters

appletbg      The applets background color, default EEEEFF
appletfg       The applets foreground color, default 000000
buttonbg     The buttons background color, default CCCCCC
buttonfg      The buttons foreground color, default 000000
textfieldbg The textfields background color, default FFFFFF
textfieldfg   The textfields foreground color, default 000000
coordbg      The coordinate systems background color, default 000000 ( this parameter is disabled in trial version )
coordfg       The coordinate systems foreground color, default FFFFFF
listbg           The function lists background color, default CCCCCC
listfg            The function lists foreground color, default 000000

Here is an example of how the applet may look if you change all the colors:

The parameters for this color scheme is :
( note that some parameters are disabled in trial version )

Layout Parameters

Note that the applet already has the prefered size, if you alter any of these
clipping may occur and the result being a useless applet.

You can experiment with these without any risk, just remove the parameters
if there is a problem and reload or restart your web browser.

Also note that the whole applets size is controlled by the width and height
attributes in the applet tag itself, if you change any of these parameters
you may need to change the whole applets size.

calcx
calcy
calcwidth
calcheight

The x, y startpoint and width, height for the calculator part of the applet.
Default 5,5,240,350

coordx
coordy
coordwidth
coordheight

The x, y startpoint and width, height for the coordinate system.
Default 250,5,350,350

listx
listy
listwidth
listheight

The x, y startpoint and width, height for the function list.
Default 601,5,50,350

Known Issues

* The x and y bounds, if you zoom in at a close range you will not see all the digits in the field
without placing your mouse in the field and then press the -> arrow button on your keyboard.
Look out for these situations since they can be confusing, especially if the bounds is
a value like 1.23456789E-3 and all you see in the field is 1.2345..
The problem is because the fields are small in order to keep the applet as compact as possible.

* The recommended use of browser for this applet is Netscape 4.x and higher
or IE 4.x and higher, the applet will work in older browsers but the result
may vary. For example, in Netscape 3.x various refresh problems was discovered.

License
You can use the demo version of the applet for a period of ten days,
if you want to keep using the applet after that you will have to purchase
the full version.
The full verson of the applet is $35 and can be payed online using a
secure server here.
The "10 DAY TRIAL VERSION" text is of course removed from the full version,
you will also be able to change all the colors.
The GraphApplet is Copyright © 1999 Patrik Lundin, plundin@kagi.com

Author Patrik Lundin, plundin@kagi.com, http://www.javathings.com