## Pivot & Gauss-Jordan Tool

### A Utility for Row Operations, Pivoting, and Row Reduction

This tool is on loan from Stefan Waner and Steven R. Costenoble at Hofstra University. It was developed in conjunction with their book **Finite Mathematics Applied to the Real World**. |

Use of this utility is quite intuitive. Just enter the matrix entries in the spreadsheet below (in fraction or decimal form; use the tab key to move from one cell to the next) and tell the program what to do. You can use as many cells as you like -- just leave unused cells blank.

- Decimal mode displays all the entries as decimals, rounded to the number of significant digits you have selected (up to 13, depending on your processor and browser).
- Fraction mode converts all decimals to fractions and displays all the tableaus (and solutions) as fractions.
- Integer Mode eliminates decimals and fractions (using the method in
*Finite Mathematics Applied to the Real World*) and displays the solution as fractions. It also reduces each row to lowest terms if you use "Pivot" or "Row Reduce".
- "Save This" saves the current matrix and mode, and "Revert to Saved" restores the saved matrix.
**Row Operations** You can use the "Row Operation" fields to either multiply a row by a constant, or replace the first-named row by a combination with the second. If you are in Integer mode and perform an operation that results in fractions, the utility will automatically switch to Fraction mode. (Press "Undo" to undo such an operation and mode change.)
- "Row Reduce" reduces the matrix to "reduced row-echelon form."

**Disclaimer: **Browsers sometimes crash when running computation-intensive Javascript code. Make sure your important work is saved before running this utility.

Last Updated:* April, 1999*

Copyright © 1999 Stefan Waner and Steven R. Costenoble