E-CodeMatrix inverse from a typed matrix — a TI-89 Titanium program
MINV89 is a TI-89 BASIC program for the TI-89 Titanium. Type a square matrix like [[4,7][2,6]]: its determinant and the exact inverse row by row, or SINGULAR when there is none.
What it asks for and what it shows
It asks for 1 value at its prompts. In the example below it shows DET, INVERSE:, R1, R2.
Example run
One of its oracle test cases: “2x2 [[4,7][2,6]]”. The inputs are typed in order, and the results are the values the case expects on the screen.
| Step | Value |
|---|---|
| You enter | |
| Input 1 | [[4,7][2,6]] |
| The screen shows | |
DET= | 10 |
| Text | INVERSE: |
R1= | {3/5 -7/10} |
R2= | {-1/5 2/5} |
How it's checked
7 test cases, each checked against an independent method. Replayed key by key on a virtual TI-89 Titanium, they make 44 checks.
How E-Code checks every program
Run it or put it on your calculator
- Open the library in the TI-89 Titanium calculator and pick “Matrix inverse from a typed matrix” (MINV89).
- Put it on your own calculator with a computer and a USB cable, or type it in by hand.
Related programs
- LU decomposition with pivoting (exact)
- Matrix inverse, exact
- LU decomposition of a typed matrix
- Cramer's rule with every determinant
- Linear system, exact answers
All TI-89 Titanium math programs · All TI-89 Titanium programs