Esempio n. 1
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def test_get_coef_multiclass_full(n_classes, n_channels, n_times):
    """Test a full example with pattern extraction."""
    from sklearn.pipeline import make_pipeline
    from sklearn.linear_model import LogisticRegression
    from sklearn.model_selection import StratifiedKFold
    data = np.zeros((10 * n_classes, n_channels, n_times))
    # Make only the first channel informative
    for ii in range(n_classes):
        data[ii * 10:(ii + 1) * 10, 0] = ii
    events = np.zeros((len(data), 3), int)
    events[:, 0] = np.arange(len(events))
    events[:, 2] = data[:, 0, 0]
    info = create_info(n_channels, 1000., 'eeg')
    epochs = EpochsArray(data, info, events, tmin=0)
    clf = make_pipeline(
        Scaler(epochs.info),
        Vectorizer(),
        LinearModel(LogisticRegression(random_state=0, multi_class='ovr')),
    )
    scorer = 'roc_auc_ovr_weighted'
    time_gen = GeneralizingEstimator(clf, scorer, verbose=True)
    X = epochs.get_data()
    y = epochs.events[:, 2]
    n_splits = 3
    cv = StratifiedKFold(n_splits=n_splits)
    scores = cross_val_multiscore(time_gen, X, y, cv=cv, verbose=True)
    want = (n_splits, )
    if n_times > 1:
        want += (n_times, n_times)
    assert scores.shape == want
    assert_array_less(0.8, scores)
    clf.fit(X, y)
    patterns = get_coef(clf, 'patterns_', inverse_transform=True)
    assert patterns.shape == (n_classes, n_channels, n_times)
    assert_allclose(patterns[:, 1:], 0., atol=1e-7)  # no other channels useful
Esempio n. 2
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def test_decim():
    """Test evoked decimation."""
    rng = np.random.RandomState(0)
    n_epochs, n_channels, n_times = 5, 10, 20
    dec_1, dec_2 = 2, 3
    decim = dec_1 * dec_2
    sfreq = 1000.
    sfreq_new = sfreq / decim
    data = rng.randn(n_epochs, n_channels, n_times)
    events = np.array([np.arange(n_epochs), [0] * n_epochs, [1] * n_epochs]).T
    info = create_info(n_channels, sfreq, 'eeg')
    info['lowpass'] = sfreq_new / float(decim)
    epochs = EpochsArray(data, info, events)
    data_epochs = epochs.copy().decimate(decim).get_data()
    data_epochs_2 = epochs.copy().decimate(decim, offset=1).get_data()
    data_epochs_3 = epochs.decimate(dec_1).decimate(dec_2).get_data()
    assert_array_equal(data_epochs, data[:, :, ::decim])
    assert_array_equal(data_epochs_2, data[:, :, 1::decim])
    assert_array_equal(data_epochs, data_epochs_3)

    # Now let's do it with some real data
    raw = read_raw_fif(raw_fname, add_eeg_ref=False)
    events = read_events(event_name)
    sfreq_new = raw.info['sfreq'] / decim
    raw.info['lowpass'] = sfreq_new / 4.  # suppress aliasing warnings
    picks = pick_types(raw.info, meg=True, eeg=True, exclude=())
    epochs = Epochs(raw, events, 1, -0.2, 0.5, picks=picks, preload=True,
                    add_eeg_ref=False)
    for offset in (0, 1):
        ev_ep_decim = epochs.copy().decimate(decim, offset).average()
        ev_decim = epochs.average().decimate(decim, offset)
        expected_times = epochs.times[offset::decim]
        assert_allclose(ev_decim.times, expected_times)
        assert_allclose(ev_ep_decim.times, expected_times)
        expected_data = epochs.get_data()[:, :, offset::decim].mean(axis=0)
        assert_allclose(ev_decim.data, expected_data)
        assert_allclose(ev_ep_decim.data, expected_data)
        assert_equal(ev_decim.info['sfreq'], sfreq_new)
        assert_array_equal(ev_decim.times, expected_times)
              mode='mean',
              vmin=vmin,
              vmax=vmax,
              title='Using Morlet wavelets and EpochsTFR',
              show=False)

###############################################################################
# Operating on arrays
# -------------------
#
# MNE also has versions of the functions above which operate on numpy arrays
# instead of MNE objects. They expect inputs of the shape
# ``(n_epochs, n_channels, n_times)``. They will also return a numpy array
# of shape ``(n_epochs, n_channels, n_freqs, n_times)``.

power = tfr_array_morlet(epochs.get_data(),
                         sfreq=epochs.info['sfreq'],
                         freqs=freqs,
                         n_cycles=n_cycles,
                         output='avg_power')
# Baseline the output
rescale(power, epochs.times, (0., 0.1), mode='mean', copy=False)
fig, ax = plt.subplots()
mesh = ax.pcolormesh(epochs.times * 1000,
                     freqs,
                     power[0],
                     cmap='RdBu_r',
                     vmin=vmin,
                     vmax=vmax)
ax.set_title('TFR calculated on a numpy array')
ax.set(ylim=freqs[[0, -1]], xlabel='Time (ms)')
power = tfr_morlet(epochs, freqs=freqs,
                   n_cycles=n_cycles, return_itc=False, average=False)
print(type(power))
avgpower = power.average()
avgpower.plot([0], baseline=(0., 0.1), mode='mean', vmin=vmin, vmax=vmax,
              title='Using Morlet wavelets and EpochsTFR', show=False)

###############################################################################
# Operating on arrays
# -------------------
#
# MNE also has versions of the functions above which operate on numpy arrays
# instead of MNE objects. They expect inputs of the shape
# ``(n_epochs, n_channels, n_times)``. They will also return a numpy array
# of shape ``(n_epochs, n_channels, n_frequencies, n_times)``.

power = tfr_array_morlet(epochs.get_data(), sfreq=epochs.info['sfreq'],
                         frequencies=freqs, n_cycles=n_cycles,
                         output='avg_power')
# Baseline the output
rescale(power, epochs.times, (0., 0.1), mode='mean', copy=False)
fig, ax = plt.subplots()
mesh = ax.pcolormesh(epochs.times * 1000, freqs, power[0],
                     cmap='RdBu_r', vmin=vmin, vmax=vmax)
ax.set_title('TFR calculated on a numpy array')
ax.set(ylim=freqs[[0, -1]], xlabel='Time (ms)')
fig.colorbar(mesh)
plt.tight_layout()

plt.show()
power = tfr_morlet(epochs, freqs=freqs,
                   n_cycles=n_cycles, return_itc=False, average=False)
print(type(power))
avgpower = power.average()
avgpower.plot([0], baseline=(0., 0.1), mode='mean', vmin=vmin, vmax=vmax,
              title='Using Morlet wavelets and EpochsTFR', show=False)

###############################################################################
# Operating on arrays
# -------------------
#
# MNE also has versions of the functions above which operate on numpy arrays
# instead of MNE objects. They expect inputs of the shape
# ``(n_epochs, n_channels, n_times)``. They will also return a numpy array
# of shape ``(n_epochs, n_channels, n_freqs, n_times)``.

power = tfr_array_morlet(epochs.get_data(), sfreq=epochs.info['sfreq'],
                         freqs=freqs, n_cycles=n_cycles,
                         output='avg_power')
# Baseline the output
rescale(power, epochs.times, (0., 0.1), mode='mean', copy=False)
fig, ax = plt.subplots()
mesh = ax.pcolormesh(epochs.times * 1000, freqs, power[0],
                     cmap='RdBu_r', vmin=vmin, vmax=vmax)
ax.set_title('TFR calculated on a numpy array')
ax.set(ylim=freqs[[0, -1]], xlabel='Time (ms)')
fig.colorbar(mesh)
plt.tight_layout()

plt.show()
Esempio n. 6
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    raw = mne.io.read_raw_fif(raw_fname, preload=True)
    raw.pick_types(meg='grad', eog=True)  # we just look at gradiometers

    # bandpass filter and compute Hilbert
    raw.filter(fmin, fmax, n_jobs=1,  # use more jobs to speed up.
               l_trans_bandwidth=1,  # make sure filter params are the same
               h_trans_bandwidth=1,  # in each band and skip "auto" option.
               fir_design='firwin')
    raw.apply_hilbert(n_jobs=1, envelope=False)

    epochs = mne.Epochs(raw, events, event_id, tmin, tmax, baseline=baseline,
                        reject=dict(grad=4000e-13, eog=350e-6), preload=True)
    # remove evoked response and get analytic signal (envelope)
    epochs.subtract_evoked()  # for this we need to construct new epochs.
    epochs = mne.EpochsArray(
        data=np.abs(epochs.get_data()), info=epochs.info, tmin=epochs.tmin)
    # now average and move on
    frequency_map.append(((band, fmin, fmax), epochs))

beta_data = frequency_map[2][1]
beta_sim = sd.make_sim_data(beta_data, order=17)
alpha_data = frequency_map[1][1]
alpha_sim = sd.make_sim_data(alpha_data, order=17)
theta_data = frequency_map[0][1]
theta_sim = sd.make_sim_data(theta_data, order=17)
gamma_data = frequency_map[3][1]
gamma_sim = sd.make_sim_data(theta_data, order=17)

beta_sim.average().plot_joint()
beta_data.average().plot_joint()
beta_diff = mne.combine_evoked([beta_data.average(), -beta_sim.average()],