Comments:

This is a demonstration of a program, Reg, that does curve-fitting and shows the results in GeoGebra.
It is published here in the hope that some GeoGebra users might find it useful.

Files:

reg.zip

(GeoGebra itself not included.)

Applet:

html-page:	Have a look at the <applet>-tags with View, Source in your browser
reg.jar:	The regression program files
reg.properties:	A setup-file for the text in the regression program
geogebra.jar (at least):	GeoGebra itself.

Application:

The regression program and GeoGebra can be run locally as an application by running the reg.bat - file (or reg.sh).
(There are some problems with the ToolBar in Windows, works in Mac...)

Documentation:

The regression program works with the points in the textarea to the left in the regression window.

These points can be sent to GeoGebra with the "Send points to Ggb" - button.
The points will be included in a list with the given list-name.
(If no list name given, "RegList" will be used as list-name.)

If the points have names, see further down, the points with names will be sent to GeoGebra individually.

Points can also be fetched from GeoGebra with the "Get points from Ggb" - button, but have to be in a list with the given name.
(If no list name given, all points in GeoGebra will be fetched.)

Points can also be loaded and saved to a local file with the respective buttons, or simply be pasted into the textarea with copy-paste (Ctrl-C and Ctrl-V) from somewhere else.

Regression is done with the "Do regression!" - button, the function will be sent to GeoGebra.

Points-file format:

The program should be able to understand both comma-, semicolon- and white-separated data,
like the examples below: (Try to copy and paste the examples into the textarea and try the regression.)

Data points: (this line is taken as a comment) 1.0 1.0 2.0,3.0 3.0;5.0 4.0 9.0

or

Data points: (this line is taken as a comment) A 1.0 1.0 B,2.0,3.0 C;3.0;5.0 D 4.0 9.0

Important:

With named points you can move the points in GeoGebra, but to do a new regression, you have to get the ponts from GeoGebra back to the regression program.
Remember that the regression program and GeoGebra are two different programs, not one, integrated program, and that the regression works with the points in the textarea, not the points in GeoGebra.
(This is the reason why I am hoping for a plugin-system in GeoGebra in the future :-) )