@slow_test
@testing.requires_testing_data
def test_volume_stc():
    """Test volume STCs
    """
    tempdir = _TempDir()
    N = 100
    data = np.arange(N)[:, np.newaxis]
    datas = [data, data, np.arange(2)[:, np.newaxis]]
    vertno = np.arange(N)
    vertnos = [vertno, vertno[:, np.newaxis], np.arange(2)[:, np.newaxis]]
    vertno_reads = [vertno, vertno, np.arange(2)]
    for data, vertno, vertno_read in zip(datas, vertnos, vertno_reads):
        stc = VolSourceEstimate(data, vertno, 0, 1)
        fname_temp = op.join(tempdir, 'temp-vl.stc')
        stc_new = stc
        for _ in range(2):
            stc_new.save(fname_temp)
            stc_new = read_source_estimate(fname_temp)
            assert_true(isinstance(stc_new, VolSourceEstimate))
            assert_array_equal(vertno_read, stc_new.vertices)
            assert_array_almost_equal(stc.data, stc_new.data)

    # now let's actually read a MNE-C processed file
    stc = read_source_estimate(fname_vol, 'sample')
    assert_true(isinstance(stc, VolSourceEstimate))

    assert_true('sample' in repr(stc))
    stc_new = stc
    assert_raises(ValueError, stc.save, fname_vol, ftype='whatever')
    for _ in range(2):
        fname_temp = op.join(tempdir, 'temp-vol.w')
        stc_new.save(fname_temp, ftype='w')
        stc_new = read_source_estimate(fname_temp)
        assert_true(isinstance(stc_new, VolSourceEstimate))
        assert_array_equal(stc.vertices, stc_new.vertices)
        assert_array_almost_equal(stc.data, stc_new.data)

    # save the stc as a nifti file and export
    try:
        import nibabel as nib
        with warnings.catch_warnings(record=True):
            warnings.simplefilter('always')
            src = read_source_spaces(fname_vsrc)
        vol_fname = op.join(tempdir, 'stc.nii.gz')
        stc.save_as_volume(vol_fname, src,
                           dest='surf', mri_resolution=False)
        with warnings.catch_warnings(record=True):  # nib<->numpy
            img = nib.load(vol_fname)
        assert_true(img.shape == src[0]['shape'] + (len(stc.times),))

        with warnings.catch_warnings(record=True):  # nib<->numpy
            t1_img = nib.load(fname_t1)
        stc.save_as_volume(op.join(tempdir, 'stc.nii.gz'), src,
                           dest='mri', mri_resolution=True)
        with warnings.catch_warnings(record=True):  # nib<->numpy
            img = nib.load(vol_fname)
        assert_true(img.shape == t1_img.shape + (len(stc.times),))
        assert_array_almost_equal(img.get_affine(), t1_img.get_affine(),
                                  decimal=5)

        # export without saving
        img = stc.as_volume(src, dest='mri', mri_resolution=True)
        assert_true(img.shape == t1_img.shape + (len(stc.times),))
        assert_array_almost_equal(img.get_affine(), t1_img.get_affine(),
                                  decimal=5)

    except __HOLE__:
        print('Save as nifti test skipped, needs NiBabel')
dataset/ETHPy150Open mne-tools/mne-python/mne/tests/test_source_estimate.py/test_volume_stc