Lecture 6: Matrices

A matrix is an array of elements that follow certain rules:

We use square brackets to enclose the array.

A matrix has rows and columns, and is said to be of order .

Always mention the rows first. Thus, the above example is

Examples

is

is

is

is

A matrix is square if the # of rows == # of columns.

Some common square matrices:

In computer graphics, we most commonly use square , , and matrices.

Operations

Two matrices are equal if

If , then and .

Addition and Subtraction

Addition and subtraction of matrices is defined by addition and subtraction of corresponding elements.

We can only add and subtract matrices of the same order.