def _polar_to_cartesian(theta, r):
 x = (r * np.cos(theta))
 y = (r * np.sin(theta))
 return (x, y)

def _polar_to_cartesian ( theta , r ) : x = ( r * np . cos ( theta ) ) y = ( r * np . sin ( theta ) ) return ( x , y )
transform polar coordinates to cartesian .