def lineSlope(p1, p2):
    slope = (p2[1] - p1[1]) / (p2[0] - p1[0])
    return slope

def slopeAngle(p1, p2):
    slope  = lineSlope(p1, p2)
    radian = np.arctan(slope)
    return radian

def angleDegree(radian):
    theta = int(radian * 180 / np.pi) % 360
    return theta