_math.py 文件源码

def vector_angle_in_degrees(v):
    '''
    Given a vector, returns its elevation angle in degrees (-180..180).

    >>> vector_angle_in_degrees([1, 0])
    0.0
    >>> vector_angle_in_degrees([1, 1])
    45.0
    >>> vector_angle_in_degrees([0, 1])
    90.0
    >>> vector_angle_in_degrees([-1, 1])
    135.0
    >>> vector_angle_in_degrees([-1, 0])
    180.0
    >>> vector_angle_in_degrees([-1, -1])
    -135.0
    >>> vector_angle_in_degrees([0, -1])
    -90.0
    >>> vector_angle_in_degrees([1, -1])
    -45.0
    '''
    return np.arctan2(v[1], v[0]) * 180 / np.pi