Advantage Pac Matrix manipulaltions (simple version)

The Advantage Pac has quite extensive Matrix handling functions, mostly beyond anything I ever would need….

The simple MATRX program allows the entry of a square matrix (real or complex), and can calculate the INVERSE and DETERMINANT of it.

The square matrix entered can be the coefficients of a set of simultaneous equations, and entering a second matrix allows the system to be solved.

| 2  -3 |
| -4  8 |

Run the MATRX program ( XEQ ALPHA MATRX ALPHA)

Options presented :

RL  CX

Press RL A

Option presented :

ORDER=?

2R/S

Options presented:

A  I  DT  B  SE

A

Enter the Matrix elements

2 R/S
3 CHS R/S
4 CHS R/S
8 R/S

Options presented :

A  I  DT  B  SE

If A is part of a system of equations, for example

2x - 3y = 6
-4x + 8y = -2

Then enter matrix B

| 6 |
|-2 |

B

6 R/S
2 CHS R/S

Solve the System of Equations with SE

SE

Result is now in B

B

1:1 = 10.5 R/S
2:1 = 5 R/S

This means if

2x - 3y = 6
-4x + 8y = -2

Then X = 10.5 and y = 5

Check

(2 * 10.5) - (3*5) = 6
-(4 * 10.5) + (8 * 5) = -2

CORRECT!

A now holds the LU-Decomposition version of the original A To restore the contents of A to normal simply INVERT A twice

I I

Check A

A

1:1 = 2.00
1:2 = -3.00
2:1 = -4.00
2:2 = 8.00

Find the Determinant of A

DT

DET = 4.00

That's pretty much all for MATRX with a real matrix.

You can chose CX at the beginning, and enter the Real and Imaginary parts of each Matrix element if you are dealing with a complex matrix.

— John Pumford-Green 05/08/22 11:55