import math
import numpy as np

def rotation_matrix_to_euler_zyx(R):
    if abs(R[2,0]) != 1:
        theta = -math.asin(R[2,0])
        cos_theta = math.cos(theta)
        phi = math.atan2(R[2,1]/cos_theta, R[2,2]/cos_theta)
        psi = math.atan2(R[1,0]/cos_theta, R[0,0]/cos_theta)
    else:
        phi = 0
        if R[2,0] == -1:
            theta = math.pi/2
            psi = phi + math.atan2(R[0,1], R[0,2])
        else:
            theta = -math.pi/2
            psi = -phi + math.atan2(-R[0,1], -R[0,2])
    return phi, theta, psi  # roll, pitch, yaw


R = np.array([[-1, 0, 0],
              [0,  0, -1],
              [0,  -1, 0]])

roll, pitch, yaw = rotation_matrix_to_euler_zyx(R)
print("roll:", roll, "pitch:", pitch, "yaw:", yaw)