Exemplo n.º 1
0
def test_simulate_evoked():
    """ Test simulation of evoked data """

    raw = Raw(raw_fname)
    fwd = read_forward_solution(fwd_fname, force_fixed=True)
    fwd = pick_types_forward(fwd, meg=True, eeg=True, exclude=raw.info['bads'])
    cov = read_cov(cov_fname)

    evoked_template = read_evokeds(ave_fname, condition=0, baseline=None)
    evoked_template.pick_types(meg=True, eeg=True, exclude=raw.info['bads'])

    snr = 6  # dB
    tmin = -0.1
    sfreq = 1000.  # Hz
    tstep = 1. / sfreq
    n_samples = 600
    times = np.linspace(tmin, tmin + n_samples * tstep, n_samples)

    # Generate times series for 2 dipoles
    stc = simulate_sparse_stc(fwd['src'], n_dipoles=2, times=times)
    stc._data *= 1e-9

    # Generate noisy evoked data
    iir_filter = [1, -0.9]
    evoked = simulate_evoked(fwd, stc, evoked_template.info, cov, snr,
                             tmin=0.0, tmax=0.2, iir_filter=iir_filter)
    assert_array_almost_equal(evoked.times, stc.times)
    assert_true(len(evoked.data) == len(fwd['sol']['data']))

    # make a vertex that doesn't exist in fwd, should throw error
    stc_bad = stc.copy()
    mv = np.max(fwd['src'][0]['vertno'][fwd['src'][0]['inuse']])
    stc_bad.vertices[0][0] = mv + 1

    assert_raises(RuntimeError, simulate_evoked, fwd, stc_bad,
                  evoked_template.info, cov, snr, tmin=0.0, tmax=0.2)
    evoked_1 = simulate_evoked(fwd, stc, evoked_template.info, cov, np.inf,
                               tmin=0.0, tmax=0.2)
    evoked_2 = simulate_evoked(fwd, stc, evoked_template.info, cov, np.inf,
                               tmin=0.0, tmax=0.2)
    assert_array_equal(evoked_1.data, evoked_2.data)

    # test snr definition in dB
    evoked_noise = simulate_evoked(fwd, stc, evoked_template.info, cov,
                                   snr=snr, tmin=None, tmax=None,
                                   iir_filter=None)
    evoked_clean = simulate_evoked(fwd, stc, evoked_template.info, cov,
                                   snr=np.inf, tmin=None, tmax=None,
                                   iir_filter=None)
    noise = evoked_noise.data - evoked_clean.data

    empirical_snr = 10 * np.log10(np.mean((evoked_clean.data ** 2).ravel()) /
                                  np.mean((noise ** 2).ravel()))

    assert_almost_equal(snr, empirical_snr, decimal=5)

    cov['names'] = cov.ch_names[:-2]  # Error channels are different.
    assert_raises(ValueError, simulate_evoked, fwd, stc, evoked_template.info,
                  cov, snr=3., tmin=None, tmax=None, iir_filter=None)
Exemplo n.º 2
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def _make_stc(raw, src):
    """Helper to make a STC."""
    seed = 42
    sfreq = raw.info['sfreq']  # Hz
    tstep = 1. / sfreq
    n_samples = len(raw.times) // 10
    times = np.arange(0, n_samples) * tstep
    stc = simulate_sparse_stc(src, 10, times, random_state=seed)
    return stc
Exemplo n.º 3
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def test_simulate_evoked():
    """Test simulation of evoked data."""

    raw = read_raw_fif(raw_fname)
    fwd = read_forward_solution(fwd_fname)
    fwd = convert_forward_solution(fwd, force_fixed=True, use_cps=False)
    fwd = pick_types_forward(fwd, meg=True, eeg=True, exclude=raw.info['bads'])
    cov = read_cov(cov_fname)

    evoked_template = read_evokeds(ave_fname, condition=0, baseline=None)
    evoked_template.pick_types(meg=True, eeg=True, exclude=raw.info['bads'])

    cov = regularize(cov, evoked_template.info)
    nave = evoked_template.nave

    tmin = -0.1
    sfreq = 1000.  # Hz
    tstep = 1. / sfreq
    n_samples = 600
    times = np.linspace(tmin, tmin + n_samples * tstep, n_samples)

    # Generate times series for 2 dipoles
    stc = simulate_sparse_stc(fwd['src'], n_dipoles=2, times=times,
                              random_state=42)

    # Generate noisy evoked data
    iir_filter = [1, -0.9]
    evoked = simulate_evoked(fwd, stc, evoked_template.info, cov,
                             iir_filter=iir_filter, nave=nave)
    assert_array_almost_equal(evoked.times, stc.times)
    assert_true(len(evoked.data) == len(fwd['sol']['data']))
    assert_equal(evoked.nave, nave)

    # make a vertex that doesn't exist in fwd, should throw error
    stc_bad = stc.copy()
    mv = np.max(fwd['src'][0]['vertno'][fwd['src'][0]['inuse']])
    stc_bad.vertices[0][0] = mv + 1

    assert_raises(RuntimeError, simulate_evoked, fwd, stc_bad,
                  evoked_template.info, cov)
    evoked_1 = simulate_evoked(fwd, stc, evoked_template.info, cov,
                               nave=np.inf)
    evoked_2 = simulate_evoked(fwd, stc, evoked_template.info, cov,
                               nave=np.inf)
    assert_array_equal(evoked_1.data, evoked_2.data)

    # Test the equivalence snr to nave
    with warnings.catch_warnings(record=True):  # deprecation
        evoked = simulate_evoked(fwd, stc, evoked_template.info, cov,
                                 snr=6, random_state=42)
    assert_allclose(np.linalg.norm(evoked.data, ord='fro'),
                    0.00078346820226502716)

    cov['names'] = cov.ch_names[:-2]  # Error channels are different.
    assert_raises(ValueError, simulate_evoked, fwd, stc, evoked_template.info,
                  cov, nave=nave, iir_filter=None)
Exemplo n.º 4
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def test_simulate_evoked():
    """Test simulation of evoked data."""
    raw = read_raw_fif(raw_fname)
    fwd = read_forward_solution(fwd_fname)
    fwd = convert_forward_solution(fwd, force_fixed=True, use_cps=False)
    fwd = pick_types_forward(fwd, meg=True, eeg=True, exclude=raw.info['bads'])
    cov = read_cov(cov_fname)

    evoked_template = read_evokeds(ave_fname, condition=0, baseline=None)
    evoked_template.pick_types(meg=True, eeg=True, exclude=raw.info['bads'])

    cov = regularize(cov, evoked_template.info)
    nave = evoked_template.nave

    tmin = -0.1
    sfreq = 1000.  # Hz
    tstep = 1. / sfreq
    n_samples = 600
    times = np.linspace(tmin, tmin + n_samples * tstep, n_samples)

    # Generate times series for 2 dipoles
    stc = simulate_sparse_stc(fwd['src'], n_dipoles=2, times=times,
                              random_state=42)

    # Generate noisy evoked data
    iir_filter = [1, -0.9]
    evoked = simulate_evoked(fwd, stc, evoked_template.info, cov,
                             iir_filter=iir_filter, nave=nave)
    assert_array_almost_equal(evoked.times, stc.times)
    assert len(evoked.data) == len(fwd['sol']['data'])
    assert_equal(evoked.nave, nave)
    assert len(evoked.info['projs']) == len(cov['projs'])
    evoked_white = whiten_evoked(evoked, cov)
    assert abs(evoked_white.data[:, 0].std() - 1.) < 0.1

    # make a vertex that doesn't exist in fwd, should throw error
    stc_bad = stc.copy()
    mv = np.max(fwd['src'][0]['vertno'][fwd['src'][0]['inuse']])
    stc_bad.vertices[0][0] = mv + 1

    pytest.raises(RuntimeError, simulate_evoked, fwd, stc_bad,
                  evoked_template.info, cov)
    evoked_1 = simulate_evoked(fwd, stc, evoked_template.info, cov,
                               nave=np.inf)
    evoked_2 = simulate_evoked(fwd, stc, evoked_template.info, cov,
                               nave=np.inf)
    assert_array_equal(evoked_1.data, evoked_2.data)

    cov['names'] = cov.ch_names[:-2]  # Error channels are different.
    with pytest.raises(RuntimeError, match='Not all channels present'):
        simulate_evoked(fwd, stc, evoked_template.info, cov)
Exemplo n.º 5
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def test_metrics():
    """Test simulation metrics"""
    src = read_source_spaces(src_fname)
    times = np.arange(600) / 1000.
    rng = np.random.RandomState(42)
    stc1 = simulate_sparse_stc(src, n_dipoles=2, times=times, random_state=rng)
    stc2 = simulate_sparse_stc(src, n_dipoles=2, times=times, random_state=rng)
    E1_rms = source_estimate_quantification(stc1, stc1, metric='rms')
    E2_rms = source_estimate_quantification(stc2, stc2, metric='rms')
    E1_cos = source_estimate_quantification(stc1, stc1, metric='cosine')
    E2_cos = source_estimate_quantification(stc2, stc2, metric='cosine')

    # ### Tests to add
    assert_true(E1_rms == 0.)
    assert_true(E2_rms == 0.)
    assert_almost_equal(E1_cos, 0.)
    assert_almost_equal(E2_cos, 0.)
    stc_bad = stc2.copy().crop(0, 0.5)
    assert_raises(ValueError, source_estimate_quantification, stc1, stc_bad)
    stc_bad = stc2.copy()
    stc_bad.tmin -= 0.1
    assert_raises(ValueError, source_estimate_quantification, stc1, stc_bad)
    assert_raises(ValueError, source_estimate_quantification, stc1, stc2,
                  metric='foo')
Exemplo n.º 6
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def test_simulate_evoked():
    """ Test simulation of evoked data """

    raw = Raw(raw_fname)
    fwd = read_forward_solution(fwd_fname, force_fixed=True)
    fwd = pick_types_forward(fwd, meg=True, eeg=True, exclude=raw.info['bads'])
    cov = read_cov(cov_fname)

    evoked_template = read_evokeds(ave_fname, condition=0, baseline=None)
    evoked_template.pick_types(meg=True, eeg=True, exclude=raw.info['bads'])

    snr = 6  # dB
    tmin = -0.1
    sfreq = 1000.  # Hz
    tstep = 1. / sfreq
    n_samples = 600
    times = np.linspace(tmin, tmin + n_samples * tstep, n_samples)

    # Generate times series for 2 dipoles
    stc = simulate_sparse_stc(fwd['src'], n_dipoles=2, times=times)
    stc._data *= 1e-9

    # Generate noisy evoked data
    iir_filter = [1, -0.9]
    evoked = simulate_evoked(fwd, stc, evoked_template.info, cov, snr,
                             tmin=0.0, tmax=0.2, iir_filter=iir_filter)
    assert_array_almost_equal(evoked.times, stc.times)
    assert_true(len(evoked.data) == len(fwd['sol']['data']))

    # make a vertex that doesn't exist in fwd, should throw error
    stc_bad = stc.copy()
    mv = np.max(fwd['src'][0]['vertno'][fwd['src'][0]['inuse']])
    stc_bad.vertices[0][0] = mv + 1
    assert_raises(RuntimeError, simulate_evoked, fwd, stc_bad,
                  evoked_template.info, cov, snr, tmin=0.0, tmax=0.2)
    evoked_1 = simulate_evoked(fwd, stc, evoked_template.info, cov, np.inf,
                               tmin=0.0, tmax=0.2)
    evoked_2 = simulate_evoked(fwd, stc, evoked_template.info, cov, np.inf,
                               tmin=0.0, tmax=0.2)
    assert_array_equal(evoked_1.data, evoked_2.data)
Exemplo n.º 7
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labels = [mne.read_label(data_path + '/MEG/sample/labels/%s.label' % ln)
          for ln in label_names]

###############################################################################
# Generate source time courses from 2 dipoles and the correspond evoked data

times = np.arange(300, dtype=np.float) / raw.info['sfreq'] - 0.1
rng = np.random.RandomState(42)


def data_fun(times):
    """Function to generate random source time courses"""
    return (1e-9 * np.sin(30. * times) *
            np.exp(- (times - 0.15 + 0.05 * rng.randn(1)) ** 2 / 0.01))

stc = simulate_sparse_stc(fwd['src'], n_dipoles=2, times=times,
                          random_state=42, labels=labels, data_fun=data_fun)

###############################################################################
# Generate noisy evoked data
picks = mne.pick_types(raw.info, meg=True, exclude='bads')
iir_filter = fit_iir_model_raw(raw, order=5, picks=picks, tmin=60, tmax=180)[1]
snr = 6.  # dB
evoked = simulate_evoked(fwd, stc, info, cov, snr, iir_filter=iir_filter)

###############################################################################
# Plot
plot_sparse_source_estimates(fwd['src'], stc, bgcolor=(1, 1, 1),
                             opacity=0.5, high_resolution=True)

plt.figure()
plt.psd(evoked.data[0])
Exemplo n.º 8
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    """Generate time-staggered sinusoids at harmonics of 10Hz"""
    global n
    n_samp = len(times)
    window = np.zeros(n_samp)
    start, stop = [int(ii * float(n_samp) / (2 * n_dipoles))
                   for ii in (2 * n, 2 * n + 1)]
    window[start:stop] = 1.
    n += 1
    data = 25e-9 * np.sin(2. * np.pi * 10. * n * times)
    data *= window
    return data


times = raw.times[:int(raw.info['sfreq'] * epoch_duration)]
src = read_source_spaces(src_fname)
stc = simulate_sparse_stc(src, n_dipoles=n_dipoles, times=times,
                          data_fun=data_fun, random_state=0)
# look at our source data
fig, ax = plt.subplots(1)
ax.plot(times, 1e9 * stc.data.T)
ax.set(ylabel='Amplitude (nAm)', xlabel='Time (sec)')
mne.viz.utils.plt_show()

##############################################################################
# Simulate raw data
raw_sim = simulate_raw(raw, stc, trans_fname, src, bem_fname, cov='simple',
                       iir_filter=[0.2, -0.2, 0.04], ecg=True, blink=True,
                       n_jobs=1, verbose=True)
raw_sim.plot()

##############################################################################
# Plot evoked data
Exemplo n.º 9
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    n_samp = len(times)
    window = np.zeros(n_samp)
    start, stop = [int(ii * float(n_samp) / (2 * n_dipoles))
                   for ii in (2 * n, 2 * n + 1)]
    window[start:stop] = 1.
    n += 1
    data = 25e-9 * np.sin(2. * np.pi * 10. * n * times)
    data *= window
    return data

times = raw_nrm.times[:int(raw_nrm.info['sfreq'] * epoch_duration)]
# stc = simulate_sparse_stc(src, n_dipoles=n_dipoles, times=times,
#                           data_fun=data_fun, random_state=0)

stc = simulate_sparse_stc(src, times=times, n_dipoles=n_dipoles,
                          data_fun=data_fun,
                          labels=labels_to_sim,
                          random_state=0)

print stc.data.max()

# look at our source data
fig, ax = plt.subplots(1)
ax.plot(times, 1e9 * stc.data.T)
ax.set(ylabel='Amplitude (nAm)', xlabel='Time (sec)')
fig.show()

##############################################################################
# Simulate raw data
raw_sim = simulate_raw(raw_nrm, stc, trans_nrm, src, bem_fname, cov='simple',
                       iir_filter=[0.2, -0.2, 0.04], ecg=True, blink=True,
                       n_jobs=2, verbose=True)
Exemplo n.º 10
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closes_vertnos = closest_nodes(stim_coords['surf'], surf[0], fwd['src'][0]['vertno'])
stim_vert = surf[0][closes_vertnos]

pulse = 5e-6
def data_fun(times):
    data = np.hstack((np.repeat(0, 1000), -pulse, -pulse, pulse, pulse, np.repeat(0, 997)))
    return data

times = np.linspace(-0.5, 0.5, 2001)


lab = mne.Label(closes_vertnos, subject=subj,
                pos=stim_vert, hemi='lh', name='stim')


stc = simulate_sparse_stc(fwd1['src'], n_dipoles=1, times=times, location='center', subject=subj,
                          subjects_dir=subjects_dir, random_state=42, labels=[lab], data_fun=data_fun)


plot_sparse_source_estimates(fwd1['src'], stc, high_resolution=True)

fwd['src'].plot(trans=trans, subjects_dir=subjects_dir)

info['sfreq'] = 2000
#iir_filter = fit_iir_model_raw(raw, order=5, picks=picks, tmin=60, tmax=180)[1]
nave = 30  # simulate average of 100 epochs
evoked_sim = simulate_evoked(fwd, stc, info, cov, nave=nave, use_cps=True,
                             iir_filter=None)

evoked_ds = evoked_sim.copy()
evoked_ds.filter(None, 400, method='iir', iir_params=None)
evoked_ds.resample(1000)