@testing.requires_testing_data
def test_inverse_operator_noise_cov_rank():
    fwd_op = read_forward_solution_meg(fname_fwd, surf_ori=True)
    evoked = _get_evoked()
    noise_cov = read_cov(fname_cov)
    inv = make_inverse_operator(evoked.info, fwd_op, noise_cov, rank=64)
    assert_true(compute_rank_inverse(inv) == 64)

    fwd_op = read_forward_solution_eeg(fname_fwd, surf_ori=True)
    inv = make_inverse_operator(evoked.info, fwd_op, noise_cov,
                                rank=dict(eeg=20))
    assert_true(compute_rank_inverse(inv) == 20)
Test MNE inverse operator with a specified noise cov rank
dataset/ETHPy150Open mne-tools/mne-python/mne/minimum_norm/tests/test_inverse.py/test_inverse_operator_noise_cov_rank