Exemple #1
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def test_return_filtered():
    """Test return filtered option."""
    # Check return_filtered
    # Simulated more noise data and with broader freqquency than the desired
    X, _, _ = simulate_data(SNR=0.9, freqs_sig=[4, 13])
    sf = 250
    n_channels = X.shape[0]
    info = create_info(ch_names=n_channels, sfreq=sf, ch_types='eeg')

    filt_params_signal = dict(l_freq=freqs_sig[0], h_freq=freqs_sig[1],
                              l_trans_bandwidth=1, h_trans_bandwidth=1)
    filt_params_noise = dict(l_freq=freqs_noise[0], h_freq=freqs_noise[1],
                             l_trans_bandwidth=1, h_trans_bandwidth=1)

    # return filtered to true
    ssd = SSD(info, filt_params_signal, filt_params_noise,
              sort_by_spectral_ratio=False, return_filtered=True)
    ssd.fit(X)

    out = ssd.transform(X)
    psd_out, freqs = psd_array_welch(out[0], sfreq=250, n_fft=250)
    freqs_up = int(freqs[psd_out > 0.5][0]), int(freqs[psd_out > 0.5][-1])
    assert (freqs_up == freqs_sig)

    # return filtered to false
    ssd = SSD(info, filt_params_signal, filt_params_noise,
              sort_by_spectral_ratio=False, return_filtered=False)
    ssd.fit(X)

    out = ssd.transform(X)
    psd_out, freqs = psd_array_welch(out[0], sfreq=250, n_fft=250)
    freqs_up = int(freqs[psd_out > 0.5][0]), int(freqs[psd_out > 0.5][-1])
    assert (freqs_up != freqs_sig)
Exemple #2
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def test_ssd_pipeline():
    """Test if SSD works in a pipeline."""
    from sklearn.pipeline import Pipeline
    sf = 250
    X, A, S = simulate_data(n_trials=100, n_channels=20, n_samples=500)
    X_e = np.reshape(X, (100, 20, 500))
    # define bynary random output
    y = np.random.randint(2, size=100)

    info = create_info(ch_names=20, sfreq=sf, ch_types='eeg')

    filt_params_signal = dict(l_freq=freqs_sig[0],
                              h_freq=freqs_sig[1],
                              l_trans_bandwidth=4,
                              h_trans_bandwidth=4)
    filt_params_noise = dict(l_freq=freqs_noise[0],
                             h_freq=freqs_noise[1],
                             l_trans_bandwidth=4,
                             h_trans_bandwidth=4)
    ssd = SSD(info, filt_params_signal, filt_params_noise)
    csp = CSP()
    pipe = Pipeline([('SSD', ssd), ('CSP', csp)])
    pipe.set_params(SSD__n_components=5)
    pipe.set_params(CSP__n_components=2)
    out = pipe.fit_transform(X_e, y)
    assert (out.shape == (100, 2))
    assert (pipe.get_params()['SSD__n_components'] == 5)
Exemple #3
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def test_ssd():
    """Test Common Spatial Patterns algorithm on raw data."""
    X, A, S = simulate_data()
    sf = 250
    n_channels = X.shape[0]
    info = create_info(ch_names=n_channels, sfreq=sf, ch_types='eeg')
    n_components_true = 5

    # Init
    filt_params_signal = dict(l_freq=freqs_sig[0],
                              h_freq=freqs_sig[1],
                              l_trans_bandwidth=1,
                              h_trans_bandwidth=1)
    filt_params_noise = dict(l_freq=freqs_noise[0],
                             h_freq=freqs_noise[1],
                             l_trans_bandwidth=1,
                             h_trans_bandwidth=1)
    ssd = SSD(info, filt_params_signal, filt_params_noise)
    # freq no int
    freq = 'foo'
    filt_params_signal = dict(l_freq=freq,
                              h_freq=freqs_sig[1],
                              l_trans_bandwidth=1,
                              h_trans_bandwidth=1)
    filt_params_noise = dict(l_freq=freqs_noise[0],
                             h_freq=freqs_noise[1],
                             l_trans_bandwidth=1,
                             h_trans_bandwidth=1)
    with pytest.raises(TypeError, match='must be an instance '):
        ssd = SSD(info, filt_params_signal, filt_params_noise)

    # Wrongly specified noise band
    freq = 2
    filt_params_signal = dict(l_freq=freq,
                              h_freq=freqs_sig[1],
                              l_trans_bandwidth=1,
                              h_trans_bandwidth=1)
    filt_params_noise = dict(l_freq=freqs_noise[0],
                             h_freq=freqs_noise[1],
                             l_trans_bandwidth=1,
                             h_trans_bandwidth=1)
    with pytest.raises(ValueError, match='Wrongly specified '):
        ssd = SSD(info, filt_params_signal, filt_params_noise)

    # filt param no dict
    filt_params_signal = freqs_sig
    filt_params_noise = freqs_noise
    with pytest.raises(ValueError, match='must be defined'):
        ssd = SSD(info, filt_params_signal, filt_params_noise)

    # Data type
    filt_params_signal = dict(l_freq=freqs_sig[0],
                              h_freq=freqs_sig[1],
                              l_trans_bandwidth=1,
                              h_trans_bandwidth=1)
    filt_params_noise = dict(l_freq=freqs_noise[0],
                             h_freq=freqs_noise[1],
                             l_trans_bandwidth=1,
                             h_trans_bandwidth=1)
    ssd = SSD(info, filt_params_signal, filt_params_noise)
    raw = io.RawArray(X, info)

    pytest.raises(TypeError, ssd.fit, raw)

    # More than 1 channel type
    ch_types = np.reshape([['mag'] * 10, ['eeg'] * 10], n_channels)
    info_2 = create_info(ch_names=n_channels, sfreq=sf, ch_types=ch_types)

    with pytest.raises(ValueError, match='At this point SSD'):
        ssd = SSD(info_2, filt_params_signal, filt_params_noise)

    # Number of channels
    info_3 = create_info(ch_names=n_channels + 1, sfreq=sf, ch_types='eeg')
    ssd = SSD(info_3, filt_params_signal, filt_params_noise)
    pytest.raises(ValueError, ssd.fit, X)

    # Fit
    n_components = 10
    ssd = SSD(info,
              filt_params_signal,
              filt_params_noise,
              n_components=n_components)

    # Call transform before fit
    pytest.raises(AttributeError, ssd.transform, X)

    # Check outputs
    ssd.fit(X)

    assert (ssd.filters_.shape == (n_channels, n_channels))
    assert (ssd.patterns_.shape == (n_channels, n_channels))

    # Transform
    X_ssd = ssd.fit_transform(X)
    assert (X_ssd.shape[0] == n_components)
    # back and forward
    ssd = SSD(info,
              filt_params_signal,
              filt_params_noise,
              n_components=None,
              sort_by_spectral_ratio=False)
    ssd.fit(X)
    X_denoised = ssd.inverse_transform(X)
    assert_array_almost_equal(X_denoised, X)

    # Power ratio ordering
    spec_ratio, _ = ssd.get_spectral_ratio(ssd.transform(X))
    # since we now that the number of true components is 5, the relative
    # difference should be low for the first 5 components and then increases
    index_diff = np.argmax(-np.diff(spec_ratio))
    assert index_diff == n_components_true - 1

    # Check detected peaks
    # fit ssd
    n_components = n_components_true
    filt_params_signal = dict(l_freq=freqs_sig[0],
                              h_freq=freqs_sig[1],
                              l_trans_bandwidth=1,
                              h_trans_bandwidth=1)
    filt_params_noise = dict(l_freq=freqs_noise[0],
                             h_freq=freqs_noise[1],
                             l_trans_bandwidth=1,
                             h_trans_bandwidth=1)
    ssd = SSD(info,
              filt_params_signal,
              filt_params_noise,
              n_components=n_components,
              sort_by_spectral_ratio=False)
    ssd.fit(X)

    out = ssd.transform(X)
    psd_out, _ = psd_array_welch(out[0], sfreq=250, n_fft=250)
    psd_S, _ = psd_array_welch(S[0], sfreq=250, n_fft=250)
    corr = np.abs(np.corrcoef((psd_out, psd_S))[0, 1])
    assert np.abs(corr) > 0.95

    # Check pattern estimation
    # Since there is no exact ordering of the recovered patterns
    # a pair-wise greedy search will be done
    error = list()
    for ii in range(n_channels):
        corr = np.abs(np.corrcoef(ssd.patterns_[ii, :].T, A[:, 0])[0, 1])
        error.append(1 - corr)
        min_err = np.min(error)
    assert min_err < 0.3  # threshold taken from SSD original paper
Exemple #4
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def test_ssd_epoched_data():
    """Test Common Spatial Patterns algorithm on epoched data.

    Compare the outputs when raw data is used.
    """
    X, A, S = simulate_data(n_trials=100, n_channels=20, n_samples=500)
    sf = 250
    n_channels = X.shape[0]
    info = create_info(ch_names=n_channels, sfreq=sf, ch_types='eeg')
    n_components_true = 5

    # Build epochs as sliding windows over the continuous raw file

    # Epoch length is 1 second
    X_e = np.reshape(X, (100, 20, 500))

    # Fit
    filt_params_signal = dict(l_freq=freqs_sig[0],
                              h_freq=freqs_sig[1],
                              l_trans_bandwidth=4,
                              h_trans_bandwidth=4)
    filt_params_noise = dict(l_freq=freqs_noise[0],
                             h_freq=freqs_noise[1],
                             l_trans_bandwidth=4,
                             h_trans_bandwidth=4)

    # ssd on epochs
    ssd_e = SSD(info, filt_params_signal, filt_params_noise)
    ssd_e.fit(X_e)
    # ssd on raw
    ssd = SSD(info, filt_params_signal, filt_params_noise)
    ssd.fit(X)

    # Check if the 5 first 5 components are the same for both
    _, sorter_spec_e = ssd_e.get_spectral_ratio(ssd_e.transform(X_e))
    _, sorter_spec = ssd.get_spectral_ratio(ssd.transform(X))
    assert_array_equal(sorter_spec_e[:n_components_true],
                       sorter_spec[:n_components_true])
Exemple #5
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def test_sorting():
    """Test sorting learning during training."""
    X, _, _ = simulate_data(n_trials=100, n_channels=20, n_samples=500)
    # Epoch length is 1 second
    X = np.reshape(X, (100, 20, 500))
    # split data
    Xtr, Xte = X[:80], X[80:]
    sf = 250
    n_channels = Xtr.shape[1]
    info = create_info(ch_names=n_channels, sfreq=sf, ch_types='eeg')

    filt_params_signal = dict(l_freq=freqs_sig[0],
                              h_freq=freqs_sig[1],
                              l_trans_bandwidth=4,
                              h_trans_bandwidth=4)
    filt_params_noise = dict(l_freq=freqs_noise[0],
                             h_freq=freqs_noise[1],
                             l_trans_bandwidth=4,
                             h_trans_bandwidth=4)

    # check sort_by_spectral_ratio set to False
    ssd = SSD(info,
              filt_params_signal,
              filt_params_noise,
              n_components=None,
              sort_by_spectral_ratio=False)
    ssd.fit(Xtr)
    _, sorter_tr = ssd.get_spectral_ratio(ssd.transform(Xtr))
    _, sorter_te = ssd.get_spectral_ratio(ssd.transform(Xte))
    assert any(sorter_tr != sorter_te)

    # check sort_by_spectral_ratio set to True
    ssd = SSD(info,
              filt_params_signal,
              filt_params_noise,
              n_components=None,
              sort_by_spectral_ratio=True)
    ssd.fit(Xtr)

    # check sorters
    sorter_in = ssd.sorter_spec
    ssd = SSD(info,
              filt_params_signal,
              filt_params_noise,
              n_components=None,
              sort_by_spectral_ratio=False)
    ssd.fit(Xtr)
    _, sorter_out = ssd.get_spectral_ratio(ssd.transform(Xtr))

    assert all(sorter_in == sorter_out)