tt
great, so if '1/iw' is that, then it can be flipped over to give me 'iw'. what im worrying about is that each of these (x^2 + y^2) are different values, i seem a wee bit out of my depth and i'll ask my professors tommorow see what they think, but i'll troop on for a while, see if i can make some progress on this. thanks for all the help so far, i'm starting to see the problem in context