# help for tkmatrix for linux

## what is tkmatrix?

tkmatrix is an education mathematical program to manipulate matrices. Matrices are part of linear algebra.
It was developed for students to learn algorithms and test own calculation.
Therefore tkmatrix can give not even a solution but all algorithms steps as a protocol.
It can calculate with floatnumbers and fractions. Solutions and protocols can be exported to ascii, html and latex files. (other files are possible).
The math-part of tkmatrix is programmed in C++ as tcl-library and graphical interface in Tk/Tcl.
Tkmatrix can be also a frontend for Octave (A high-level interactive language for numerical computations.)
At least for linear Algebra and matrices manipulation.
Tkmatrix can load and save in octave format and run specially prepared octave scripts.

The distribution includes the program matrix too. It is pure shellprogram tkmatrix without GUI.

Full documentation is aviable only in German language. Mathematical short English documentation (mathematical part) is as `mathe_en.ps`

. For viewing use ghostview. There is also source Latex file for it.

Following mathematical operation are implemented:
- gauss reduction
- gauss-jordan reduction - make Hermite normal form
- solve linear equations (also not unique solutions)
- find basis of matrix
- find kernel of matrix - basis of the solution space of the homogeneous system
- determinant - by using gauss reduction
- tranponent
- best solution - linear regresion method
- parts of simplex method (finding of corners of simplex, reduce matrix by columns)
- simplex method - maximize function and satisfy the set of inequalities (canonical maximum problem)
- charakteristic polynom (used for eigen values)
- matrices multiplication, addition and substraction

Full mathematical and program documentation is available only in german language.
## Helpfull Things

If you want to print or preview matrices or protocols you need install Latex and ghostview (lunched as gv) on your computer. If it does not work adapt file `print.tcl`

For mark a part of matrix use SHIFT key

tkmatrix need for protocol-window many XWindows Resources (2000 Widgets for simplex protokol).
If your system have bad performance use ghostview to view protokols (Menu view/protocol preview).
You need to change preferences (menu edit/preferences) if the protocol-window do not need to be showed.

fractions are edited with a colon example 1,1,2 mean 1½