Hi,

I need an idiot's guide on how to calculate ArcTan(x,y), can somebody please help?

I have a working example (below) but have no idea how it works:

α = arctan(sin(12.0321°) * cos(23.45°), cos(12.0321°)) = 11.0639°

Incidentally, in order to calculate sin and cos (in VB Code) I have to convert the degrees to radians first - will this mess up the output or can I just convert it back into degrees again?

Thanks for looking,

Chris.