I got an error on this and I don't inderstand it:
Code:
direction = (tc /DtoR + 540)Mod(360)
all variables here are defined as numbers, DToR = cPI/180,
tc = ACos((Sin(s_lat)-Sin(f_lat)*Cos(d))/(Sin(d)*Cos(f_lat)))
Edit: - found it, direction was already declared as global, but still, the message text is not directing to the problem.