`scipy.spatial.transform._rotation:Rotation.as_matrix`

source: build-install/usr/lib/python3.14/site-packages/scipy/spatial/transform/_rotation.py:1092

Signature

def as_matrix(self) → Array

Summary

Represent as rotation matrix.

Extended Summary

3D rotations can be represented using rotation matrices, which are 3 x 3 real orthogonal matrices with determinant equal to +1 ^[1].

Returns

matrix : ndarray, shape (..., 3): Shape depends on shape of inputs used for initialization.

Notes

This function was called as_dcm before.

Examples

from scipy.spatial.transform import Rotation as R
import numpy as np

✓

Represent a single rotation:

r = R.from_rotvec([0, 0, np.pi/2])

✓

r.as_matrix()

✗

array([[ 0., -1.,  0.],
       [ 1.,  0.,  0.],
       [ 0.,  0.,  1.]])

r.as_matrix().shape

✓

(3, 3)

Represent a stack with a single rotation:

r = R.from_quat([[1, 1, 0, 0]])
r.as_matrix()
r.as_matrix().shape

✓

(1, 3, 3)

Represent multiple rotations:

r = R.from_rotvec([[np.pi/2, 0, 0], [0, 0, np.pi/2]])

✓

r.as_matrix()

✗

array([[[ 1.,  0.,  0.],
        [ 0.,  0., -1.],
        [ 0.,  1.,  0.]],

       [[ 0., -1.,  0.],
        [ 1.,  0.,  0.],
        [ 0.,  0.,  1.]]])

r.as_matrix().shape

✓

(2, 3, 3)

Aliases

scipy.spatial.transform.Rotation.as_matrix