Quaternion to rotation axis and angle
[u,alpha] = CL_rot_quat2axAng(q)
Converts a quaternion into rotation axis and angle.
Notes:
- The rotation axis returned may be undefined (%nan).
- See Conventions or CL_rot_defQuat for more details on quaternions.
Rotation axis [ux;uy;uz] (3xN)
Quaternion (dim N)
Rotation angle [rad] (1xN)
CNES - DCT/SB