# scipy.spatial.transform.Rotation.from_rotvec

Rotation.from_rotvec()

  Initialize from rotation vectors.

  A rotation vector is a 3 dimensional vector which is co-directional to the axis of rotation and whose norm gives the angle of rotation [1].

  Parameters
    rotvec array_like, shape (N, 3) or (3,)

      A single vector or a stack of vectors, where rot_vec[i] gives the ith rotation vector.

    degrees bool, optional

      If True, then the given magnitudes are assumed to be in degrees. Default is False.

      New in version 1.7.0.

  Returns
    rotation `Rotation` instance

      Object containing the rotations represented by input rotation vectors.

  References

  1

    https://en.wikipedia.org/wiki/Axis%E2%80%93angle_representation#Rotation_vector

  Examples

      >>> from scipy.spatial.transform import Rotation as R

  Initialize a single rotation:

      >>> r = R.from_rotvec(np.pi/2 * np.array([0, 0, 1]))
      >>> r.as_rotvec()
      array([0.        , 0.        , 1.57079633])
      >>> r.as_rotvec().shape
      (3,)

  Initialize a rotation in degrees, and view it in degrees:

      >>> r = R.from_rotvec(45 * np.array([0, 1, 0]), degrees=True)
      >>> r.as_rotvec(degrees=True)
      array([ 0., 45.,  0.])

  Initialize multiple rotations in one object:

      >>> r = R.from_rotvec([
      ... [0, 0, np.pi/2],
      ... [np.pi/2, 0, 0]])
      >>> r.as_rotvec()
      array([[0.        , 0.        , 1.57079633],
             [1.57079633, 0.        , 0.        ]])
      >>> r.as_rotvec().shape
      (2, 3)

  It is also possible to have a stack of a single rotaton:

      >>> r = R.from_rotvec([[0, 0, np.pi/2]])
      >>> r.as_rotvec().shape
      (1, 3)