To run the program, press [PRGM] and then select the number (or scroll down and press [ENTER]) that corresponds to PIV on your calculator. This will paste a command to home screen, after which you simply press [ENTER] to start the program.

You can enter the initial tableau into matrix [A] before starting the program, using the [MATRIX] [EDIT] window, or enter the tableau during the program's execution. It is probably faster to enter [A] before running the program.

The initial screen of the program allows 6 choices of things to do. Each is described briefly below. This program has NOT been tested very much, so be warned that it may have errors.

1. ENTER TABLEAU
   This option allows you to enter the initial tableau. It will prompt you for the number of rows and columns, and then ask for each entry one by one, starting with row 1 and ending with the bottom row. There is no way to alter "just a few entries" via the program. If you need to do that, you are best off quitting the program and using the calculator's [MATRIX] [EDIT] screen.
2. RATIOS
   This option asks you for a column index and then calculates the ratios (last column entry divided by given column entry) for each row. The ratios are displayed as a column vector (row 1 ratio on top, row 2 ratio next and so on).
3. PIVOT
   This option asks for a pivot column and pivot row and then performs a pivot on the current tableau. The results will be displayed in fraction form and you must press [ENTER] to continue (back to the main menu).
4. SHOW TABLEAU
   This option prints out a scrollable version of the current tableau (in fraction form). Once again, you must press [ENTER] to return to the main menu.
5. BACK ONE
   This option allows you to undo one pivot operation. If you try using this twice (without pivoting in between uses), you will end up with the same tableau you had after using this option once.
6. QUIT
   This option ends the program.

There are a few places in the program where the calculator has built in pauses. If you can see a "sparkling worm" in the upper right corner of your screen, you must press [ENTER] to proceed.

Here is a link to a crude text file that has the program's "code", and the actual TI-83 Plus GraphLink file that was used to create this program.