c4dynamics.states.lib.quatbody.quatbody.quat

property quatbody.quat

Gets and sets the attitude quaternion.

\[quat = [q_w, q_x, q_y, q_z]\]

The quaternion is scalar first (Hamilton convention). A set quaternion is normalized to a unit quaternion.

Parameters:

quat (numpy.array or list) – A quaternion \([q_w, q_x, q_y, q_z]\).

Returns:

out (numpy.array) – The attitude quaternion \([q_w, q_x, q_y, q_z]\).

Examples

>>> qb = c4d.quatbody(phi = 90 * c4d.d2r)
>>> qb.quat  
[0.707  0.707  0  0]

>>> qb.quat = [1, 0, 0, 1]
>>> qb.quat  
[0.707  0  0  0.707]
>>> qb.angles * c4d.r2d  
[0  0  90]