Function test_sparse_morph

mne/tests/test_morph.py:81–136

Test sparse morphing.

()

@testing.requires_testing_data
def test_sparse_morph():
    """Test sparse morphing."""
    rng = np.random.RandomState(0)
    vertices_fs = [
        np.sort(rng.permutation(np.arange(10242))[:4]),
        np.sort(rng.permutation(np.arange(10242))[:6]),
    ]
    data = rng.randn(10, 1)
    stc_fs = SourceEstimate(data, vertices_fs, 1, 1, "fsaverage")
    spheres_fs = [
        mne.read_surface(subjects_dir / "fsaverage" / "surf" / f"{hemi}.sphere.reg")[0]
        for hemi in ("lh", "rh")
    ]
    spheres_sample = [
        mne.read_surface(subjects_dir / "sample" / "surf" / f"{hemi}.sphere.reg")[0]
        for hemi in ("lh", "rh")
    ]
    morph_fs_sample = compute_source_morph(
        stc_fs,
        "fsaverage",
        "sample",
        sparse=True,
        spacing=None,
        subjects_dir=subjects_dir,
    )
    stc_sample = morph_fs_sample.apply(stc_fs)
    offset = 0
    orders = list()
    for v1, s1, v2, s2 in zip(
        stc_fs.vertices, spheres_fs, stc_sample.vertices, spheres_sample
    ):
        dists = cdist(s1[v1], s2[v2])
        order = np.argmin(dists, axis=-1)
        assert_array_less(dists[np.arange(len(order)), order], 1.5)  # mm
        orders.append(order + offset)
        offset += len(order)
    assert_allclose(stc_fs.data, stc_sample.data[np.concatenate(orders)])
    # Return
    morph_sample_fs = compute_source_morph(
        stc_sample,
        "sample",
        "fsaverage",
        sparse=True,
        spacing=None,
        subjects_dir=subjects_dir,
    )
    stc_fs_return = morph_sample_fs.apply(stc_sample)
    offset = 0
    orders = list()
    for v1, s, v2 in zip(stc_fs.vertices, spheres_fs, stc_fs_return.vertices):
        dists = cdist(s[v1], s[v2])
        order = np.argmin(dists, axis=-1)
        assert_array_less(dists[np.arange(len(order)), order], 1.5)  # mm
        orders.append(order + offset)
        offset += len(order)
    assert_allclose(stc_fs.data, stc_fs_return.data[np.concatenate(orders)])