matlab - How can I calculate the Expectation for a particular known vector?

Let us say I have a row vector $X = [x_1, x_2, x_3, \ldots, x_n]$ and another row vector $Y = [y_1, y_2, y_3, \ldots, y_n]$. I want to check whether the two vectors are statistically independent or not.

Now two vectors are said to be statistically independent if $E(X Y) = E(X) E(Y)$, where $E$ is the expectation operator.

So how would I calculate the expectation value for each of the concerned vectors?

Thank you for your suggestions - I'm really new to statistics.