c2w: what does the last operation mean?

[Junwei-LV]

`def pose_spherical(theta, phi, radius): c2w = trans_t(radius)

print(c2w)

c2w = rot_phi(phi / 180. * np.pi) @ c2w 
# print(c2w)
c2w = rot_theta(theta / 180. * np.pi) @ c2w  
# print(c2w)
c2w = torch.Tensor(np.array([[-1, 0, 0, 0], [0, 0, 1, 0], [0, 1, 0, 0], [0, 0, 0, 1]])) @ c2w
return c2w 

what does the last operation mean? why does c2w need to change to 'np.array([[-1, 0, 0, 0], [0, 0, 1, 0], [0, 1, 0, 0], [0, 0, 0, 1]]'??? thanks

[lenn-arts]

I believe the @ sign at the end is pytorch's matrix multiplication so you do not replace c2w but you rather mask it with the first tensor.