Programmed Math/Commutative

An operation is commutitive if and only if the order does not affect the result.

For example, addition is commutitive for the real numbers; thus, if $a,b$ are both real:

$a+b=b+a$

An operation that is not commutitive is subtraction over the reals; ie, the following is not true:

$a-b=b-a$