Example code to compute the wind direction for the sonic anemometer from its x and y direction wind speed. Original version by W. Skidmore. swind_dir = atan(vx/vy) * 360.0 / (2.0 * !pi) if (vx gt 0.0 and vy gt 0.0) then swind_dir = swind_dir - 180.0 if (vx lt 0.0 and vy gt 0.0) then swind_dir = swind_dir + 180.0 if (vx gt 0.0 and vy lt 0.0) then swind_dir = swind_dir + 0.0 if (vx lt 0.0 and vy lt 0.0) then swind_dir = swind_dir + 0.0 if (swind_dir gt 360.0) then swind_dir = swind_dir - 360.0 if (swind_dir lt 0.0) then swind_dir = swind_dir + 360.0 swind_dir = swind_dir + corr if (swind_dir gt 360.0) then swind_dir = swind_dir - 360.0 if (swind_dir lt 0.0) then swind_dir = swind_dir + 360.0 dir = swind_dir