Date: Jan 29, 2013 2:42 AM
Author: David Park
Subject: Re: Matrix elimination

The Presentations Application (which I sell from my web site for $50) has a
section called Student's Linear Equations. It is basically for didactic
purposes or solving small cases. It allows you to manipulate 2D matrix
structures with detailed operations such as individual operations on rows
and columns, individual column pivots, converting to echelon form with or
without upper triangular reduction. It also has display with row and column
names to give context. You can manipulate via successive displays in a
notebook, or in a Whiteboard window.

It also allows contravariant and covariant columns. There is also provision
for displaying rows or columns as equation expressions, both as regular
equations and as chemical composition equations or as chemical reactions.
There is also provision for doing linear programming simplex operations.

Presentations is a quite large Application aimed toward writing literate
notebooks with custom graphics, tables and dynamic presentations.

David Park

From: =A9er=FDch Jakub []

Dear comunity,
I'm trying to play around with the simple matrixes in Mathematica for the
first time and I have beginners question:

Does Mathematica have a function, which makes the intermediate step of
Gaussian elimination to produce just eliminated upper triangular matrix?
Function UpperTriangular only cuts the lower triangular places off (which is
not what I need) and RowReduce makes the completely reduced echelon form of
I needed the step in the middle of the RowReduce way.

Thanks in advance for any tips