Orientation is the alignment of a particle in relation to Cartesian space. It is represented in EDEM as a 3-by-3 matrix that defines the rotation of the particle from its original orientation (as defined in the Creator and assigned an identity matrix).

                                    | 1  0  0 |
A=| 0  1  0 |
| 0  0  0 |


                              | 0.765  -0.469  -0.441 |
M=| 0.469   0.875  -0.117 |
| 0.441  -0.117   0.89  |


M = [0.765, -0.469, -0.441; 0.469, 0.875, -0.117; 0.441, -0.117, 0.89]；
[r1 r2 r3] = dcm2angle(M)


r1 = -0.5500
r2 = 0.4567
r3 = -0.1307


r1 = -31.5113°
r2 = 26.1677°
r3 = -7.4892°


Q.E.D