Hi,
I'm triying to transform a vector field which is expressed with u and v componants in the same vector field expressed with velocity and direction.I have difficulties to obtain the direction. I use a (big) Compute module which tests every data and constructs the new vector.There is no problem if the first componant of the vectors is never null, the values seems correct (all between 0 and 360).But is there is a zero, an error occurs because I try to divide by 0. I don't understand why Compute doesn't make correctly the tests whereas it was correct the first time. Is it because it works with all the field? I can't find a way to do it differently. This is my Compute expression : (a.x>0 && a.y>=0) ? (180+90-atan(a.y/a.x)/deg) : ((a.x<0 && a.y>=0) ? (90+atan(a.y/(-a.x))/deg) : ((a.x<0 && a.y<0) ? (90-atan((-a.y)/(-a.x))/deg) : ((a.x>0 &&a.y<0) ? (270+atan((-a.y)/a.x)/deg) : (a.x==0 && a.y>0) ? 180 : 0))) where deg = 3.1415926535 / 180.0 Can anybody help me? Emmanuelle Lafont
