grid orientation
 

hi. how to explain a grid orientation in Fluent. There is north and east direction. I thought that i need only 3 points to orientate a grid (for example 1,1,1 tell me that a plane i faced nort, east and under 45deg to horizont isn`t it??). How to explain NORTH 0,0,1 and EAST 1,0,0? please help me with this school problem :) I don`t want to ask my daughter :)