Hi Dave,
Thanks for steering me towards the literature. I took a quick look at the perllol and see how the AoA structure can do what I want. I will look at the restof the readings tomorrow, it's getting a bit late for me on this coast.
I'm not quite sure why I was told to possibly avoid 2D arrays, it was some advice I was given at some point today. I will ask more questions to ascertain why and get back to you if you are interested.
Thanks again for the pointers, will post something later as I learn more about how to do what I want to do.