Matrix Operations

• Recall how a matrix has a height and width

4 high and 1 wide

• Matrices can only be multiplied when the width of the 1st matrix is the same as the height of the 2nd matrix

EXAMPLE

Matrix A

and Matrix B

Matrix A = 2 x 1, Matrix B = 1 x 2, What is [A] * [B]?

Check sizes: 3 x 2 * 2 x 3 (the middle numbers are the same!! So the width of the 1st matrix is the same as the height of the 2nd matrix. They are both 1. So they can be multiplied.

• Matrix multiplication calculation