scipy.spatial.transform.Rotation.__mul__¶
-
Rotation.
__mul__
(other)[source]¶ Compose this rotation with the other.
If p and q are two rotations, then the composition of ‘q followed by p’ is equivalent to p * q. In terms of DCMs, the composition can be expressed as p.as_dcm().dot(q.as_dcm()).
Parameters: - other :
Rotation
instance Object containing the rotaions to be composed with this one. Note that rotation compositions are not commutative, so p * q is different from q * p.
Returns: - composition :
Rotation
instance This function supports composition of multiple rotations at a time. The following cases are possible:
- Either p or q contains a single rotation. In this case output contains the result of composing each rotation in the other object with the single rotation.
- Both p and q contain N rotations. In this case each rotation p[i] is composed with the corresponding rotation q[i] and output contains N rotations.
Examples
>>> from scipy.spatial.transform import Rotation as R
Composition of two single rotations:
>>> p = R.from_quat([0, 0, 1, 1]) >>> q = R.from_quat([1, 0, 0, 1]) >>> p.as_dcm() array([[ 0., -1., 0.], [ 1., 0., 0.], [ 0., 0., 1.]]) >>> q.as_dcm() array([[ 1., 0., 0.], [ 0., 0., -1.], [ 0., 1., 0.]]) >>> r = p * q >>> r.as_dcm() array([[0., 0., 1.], [1., 0., 0.], [0., 1., 0.]])
Composition of two objects containing equal number of rotations:
>>> p = R.from_quat([[0, 0, 1, 1], [1, 0, 0, 1]]) >>> q = R.from_rotvec([[np.pi/4, 0, 0], [-np.pi/4, 0, np.pi/4]]) >>> p.as_quat() array([[0. , 0. , 0.70710678, 0.70710678], [0.70710678, 0. , 0. , 0.70710678]]) >>> q.as_quat() array([[ 0.38268343, 0. , 0. , 0.92387953], [-0.37282173, 0. , 0.37282173, 0.84971049]]) >>> r = p * q >>> r.as_quat() array([[ 0.27059805, 0.27059805, 0.65328148, 0.65328148], [ 0.33721128, -0.26362477, 0.26362477, 0.86446082]])
- other :