How would I go about sorting a multi-dimenstional array?

So I'm trying out some arrays and I would really like to know how I would sort the following array

array(family's Y co-ordinate, family's variable, UID if necessary)

So far it's proving to be a killer, I've looked up some sorting algorithms but I'm not too savvy on a lot of the lingo they use to define them. The sorting algorithms that looked nice were, bubble, gnome and possibly insert, I'm not sure how they apply to multi-dimensional arrays though.

I want the array to look something like this when it's sorted (leaving UID out for now):

5, 0

5, 1

5, 3

10, 0

10, 6

10, 8

etc

So primarily sorting by the Y co-ordinate ascending, but if any of the family have the same Y co-ordinate then sort by their private variable ascending

Is this possible at the moment? I'm assuming its to do with a bunch of nested loops, but it's 3:20am and my brain has imploded

Remember, I'm not that mathy, you'll have to translate into english for me

For those that are interested, I got it working, however it didn't solve my problem so its back to the drawing board

Yeah there really is no specific way to sort floats or integers, other than making up your own.

I wonder if its possible to have a object, or behavior that could do that for you.

Edit I suppose Lucid's S plug could do it, perhaps he could give an example of how that might work.