scipy.spatial.transform.Rotation.

magnitude#

Rotation.magnitude()[source]#

Get the magnitude(s) of the rotation(s).

Returns:

magnitudendarray or float: Angle(s) in radians, float if object contains a single rotation and ndarray if object contains multiple rotations. The magnitude will always be in the range [0, pi].

Notes

Array API Standard Support

magnitude has experimental support for Python Array API Standard compatible backends in addition to NumPy. Please consider testing these features by setting an environment variable SCIPY_ARRAY_API=1 and providing CuPy, PyTorch, JAX, or Dask arrays as array arguments. The following combinations of backend and device (or other capability) are supported.

Library	CPU	GPU
NumPy	✅	n/a
CuPy	n/a	✅
PyTorch	✅	✅
JAX	✅	✅
Dask	⛔	n/a

See Support for the array API standard for more information.

Examples

>>> from scipy.spatial.transform import Rotation as R
>>> import numpy as np
>>> r = R.from_quat(np.eye(4))
>>> r.as_quat()
array([[ 1., 0., 0., 0.],
       [ 0., 1., 0., 0.],
       [ 0., 0., 1., 0.],
       [ 0., 0., 0., 1.]])
>>> r.magnitude()
array([3.14159265, 3.14159265, 3.14159265, 0.        ])

Magnitude of a single rotation:

>>> r[0].magnitude()
3.141592653589793