code: def test_from_to_rigid():
      t = np.array([10, 2, 3, 0.1, 20.0, 30.0])
      mat = compose_matrix44(t)
      vec = decompose_matrix44(mat, 6)
  
      assert_array_almost_equal(t, vec)
  
      t = np.array([0, 0, 0, 180, 0.0, 0.0])
  
      mat = np.eye(4)
      mat[0, 0] = -1
  
      vec = decompose_matrix44(mat, 6)
  
      assert_array_almost_equal(-t, vec)
  
imports: import numpy
  from numpy.testing import assert_, assert_equal, assert_almost_equal, assert_array_almost_equal, assert_raises
  from dipy.align.streamlinear import compose_matrix44, decompose_matrix44, BundleSumDistanceMatrixMetric, BundleMinDistanceMatrixMetric, BundleMinDistanceMetric, StreamlineLinearRegistration, StreamlineDistanceMetric, groupwise_slr, get_unique_pairs
  from dipy.tracking.streamline import center_streamlines, unlist_streamlines, relist_streamlines, transform_streamlines, set_number_of_points, Streamlines
  from dipy.io.streamline import load_tractogram
  from dipy.core.geometry import compose_matrix
  from dipy.data import get_fnames, two_cingulum_bundles, read_five_af_bundles
  from dipy.align.bundlemin import _bundle_minimum_distance_matrix, _bundle_minimum_distance, distance_matrix_mdf
  from dipy.testing.decorators import set_random_number_generator
label_desc: Use image node_id 12 for calling a global function with example usage: test_from_to_rigid() without return types