DFOV, HFOV, VFOV calculation

import numpy as np
def calc_fov_D_H_V(f, w, h):
   return np.degrees(2*np.arctan(np.sqrt(w*w+h*h)/(2*f))), np.degrees(2*np.arctan(w/(2*f))), np.degrees(2*np.arctan(h/(2*f)))