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)
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)
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)
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)
def test_accuracy():
"""Test dipole fitting to sub-mm accuracy."""
evoked = read_evokeds(fname_evo)[0].crop(0., 0.,)
evoked.pick_types(meg=True, eeg=False)
evoked.pick_channels([c for c in evoked.ch_names[::4]])
for rad, perc_90 in zip((0.09, None), (0.002, 0.004)):
bem = make_sphere_model('auto', rad, evoked.info,
relative_radii=(0.999, 0.998, 0.997, 0.995))
src = read_source_spaces(fname_src)
fwd = make_forward_solution(evoked.info, None, src, bem)
fwd = convert_forward_solution(fwd, force_fixed=True, use_cps=True)
vertices = [src[0]['vertno'], src[1]['vertno']]
n_vertices = sum(len(v) for v in vertices)
amp = 10e-9
data = np.eye(n_vertices + 1)[:n_vertices]
data[-1, -1] = 1.
data *= amp
stc = SourceEstimate(data, vertices, 0., 1e-3, 'sample')
evoked.info.normalize_proj()
sim = simulate_evoked(fwd, stc, evoked.info, cov=None, nave=np.inf)
cov = make_ad_hoc_cov(evoked.info)
dip = fit_dipole(sim, cov, bem, min_dist=0.001)[0]
ds = []
for vi in range(n_vertices):
if vi < len(vertices[0]):
hi = 0
vertno = vi
else:
hi = 1
vertno = vi - len(vertices[0])
vertno = src[hi]['vertno'][vertno]
rr = src[hi]['rr'][vertno]
d = np.sqrt(np.sum((rr - dip.pos[vi]) ** 2))
ds.append(d)
# make sure that our median is sub-mm and the large majority are very
# close (we expect some to be off by a bit e.g. because they are
# radial)
assert_true((np.percentile(ds, [50, 90]) < [0.0005, perc_90]).all())
kwargs = dict(subjects_dir=subjects_dir, hemi='split', smoothing_steps=4,
time_unit='s', initial_time=0.05, size=1200,
views=['lat', 'med'])
clim = dict(kind='value', pos_lims=[1e-9, 1e-8, 1e-7])
figs = [mlab.figure(1), mlab.figure(2), mlab.figure(3), mlab.figure(4)]
brain_gen = stc_gen.plot(clim=clim, figure=figs, **kwargs)
###############################################################################
# Simulate sensor-space signals
# -----------------------------
#
# Use the forward solution and add Gaussian noise to simulate sensor-space
# (evoked) data from the known source-space signals. The amount of noise is
# controlled by `nave` (higher values imply less noise).
#
evoked_gen = simulate_evoked(fwd, stc_gen, evoked.info, cov, nave,
random_state=seed)
# Map the simulated sensor-space data to source-space using the inverse
# operator.
stc_inv = apply_inverse(evoked_gen, inv_op, lambda2, method=method)
###############################################################################
# Plot the point-spread of corrupted signal
# -----------------------------------------
#
# Notice that after applying the forward- and inverse-operators to the known
# point sources that the point sources have spread across the source-space.
# This spread is due to the minimum norm solution so that the signal leaks to
# nearby vertices with similar orientations so that signal ends up crossing the
# sulci and gyri.
figs = [mlab.figure(5), mlab.figure(6), mlab.figure(7), mlab.figure(8)]
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 (50e-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]
nave = 100 # simulate average of 100 epochs
evoked = simulate_evoked(fwd, stc, info, cov, nave=nave, use_cps=True,
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])
evoked.plot(time_unit='s')
evoked = mne.read_evokeds(fname_ave, condition='Right Auditory',
baseline=(None, 0))
evoked.pick_types(meg=True, eeg=False)
evoked.crop(0.07, 0.08)
# Fit a dipole
dip = mne.fit_dipole(evoked, fname_cov, fname_bem, fname_trans)[0]
# Plot the result in 3D brain
dip.plot_locations(fname_trans, 'sample', subjects_dir)
###############################################################################
# Calculate and visualise magnetic field predicted by dipole with maximum GOF
# and compare to the measured data, highlighting the ipsilateral (right) source
fwd, stc = make_forward_dipole(dip, fname_bem, evoked.info, fname_trans)
pred_evoked = simulate_evoked(fwd, stc, evoked.info, None, snr=np.inf)
# find time point with highes GOF to plot
best_time = dip.times[np.argmax(dip.gof)]
# rememeber to create a subplot for the colorbar
fig, axes = plt.subplots(nrows=1, ncols=4, figsize=[10., 3.4])
vmin, vmax = -400, 400 # make sure each plot has same colour range
# first plot the topography at the time of the best fitting (single) dipole
plot_params = dict(times=best_time, ch_type='mag', outlines='skirt',
colorbar=False)
evoked.plot_topomap(time_format='Measured field', axes=axes[0], **plot_params)
# compare this to the predicted field
pred_evoked.plot_topomap(time_format='Predicted field', axes=axes[1],
**plot_params)
baseline=(None, 0))
evoked.pick_types(meg=True, eeg=False)
evoked_full = evoked.copy()
evoked.crop(0.07, 0.08)
# Fit a dipole
dip = mne.fit_dipole(evoked, fname_cov, fname_bem, fname_trans)[0]
# Plot the result in 3D brain with the MRI image.
dip.plot_locations(fname_trans, 'sample', subjects_dir, mode='orthoview')
###############################################################################
# Calculate and visualise magnetic field predicted by dipole with maximum GOF
# and compare to the measured data, highlighting the ipsilateral (right) source
fwd, stc = make_forward_dipole(dip, fname_bem, evoked.info, fname_trans)
pred_evoked = simulate_evoked(fwd, stc, evoked.info, cov=None, nave=np.inf)
# find time point with highest GOF to plot
best_idx = np.argmax(dip.gof)
best_time = dip.times[best_idx]
print('Highest GOF %0.1f%% at t=%0.1f ms with confidence volume %0.1f cm^3'
% (dip.gof[best_idx], best_time * 1000,
dip.conf['vol'][best_idx] * 100 ** 3))
# rememeber to create a subplot for the colorbar
fig, axes = plt.subplots(nrows=1, ncols=4, figsize=[10., 3.4])
vmin, vmax = -400, 400 # make sure each plot has same colour range
# first plot the topography at the time of the best fitting (single) dipole
plot_params = dict(times=best_time, ch_type='mag', outlines='skirt',
colorbar=False, time_unit='s')
evoked.plot_topomap(time_format='Measured field', axes=axes[0], **plot_params)
def test_lcmv_vector():
"""Test vector LCMV solutions."""
info = mne.io.read_raw_fif(fname_raw).info
# For speed and for rank-deficiency calculation simplicity,
# just use grads:
info = mne.pick_info(info, mne.pick_types(info, meg='grad', exclude=()))
info.update(bads=[], projs=[])
forward = mne.read_forward_solution(fname_fwd)
forward = mne.pick_channels_forward(forward, info['ch_names'])
vertices = [s['vertno'][::100] for s in forward['src']]
n_vertices = sum(len(v) for v in vertices)
assert 5 < n_vertices < 20
amplitude = 100e-9
stc = mne.SourceEstimate(amplitude * np.eye(n_vertices), vertices,
0, 1. / info['sfreq'])
forward_sim = mne.convert_forward_solution(forward, force_fixed=True,
use_cps=True, copy=True)
forward_sim = mne.forward.restrict_forward_to_stc(forward_sim, stc)
noise_cov = mne.make_ad_hoc_cov(info)
noise_cov.update(data=np.diag(noise_cov['data']), diag=False)
evoked = simulate_evoked(forward_sim, stc, info, noise_cov, nave=1)
source_nn = forward_sim['source_nn']
source_rr = forward_sim['source_rr']
# Figure out our indices
mask = np.concatenate([np.in1d(s['vertno'], v)
for s, v in zip(forward['src'], vertices)])
mapping = np.where(mask)[0]
assert_array_equal(source_rr, forward['source_rr'][mapping])
# Don't check NN because we didn't rotate to surf ori
del forward_sim
#
# Let's do minimum norm as a sanity check (dipole_fit is slower)
#
inv = make_inverse_operator(info, forward, noise_cov, loose=1.)
stc_vector_mne = apply_inverse(evoked, inv, pick_ori='vector')
mne_ori = stc_vector_mne.data[mapping, :, np.arange(n_vertices)]
mne_ori /= np.linalg.norm(mne_ori, axis=-1)[:, np.newaxis]
mne_angles = np.rad2deg(np.arccos(np.sum(mne_ori * source_nn, axis=-1)))
assert np.mean(mne_angles) < 35
#
# Now let's do LCMV
#
data_cov = mne.make_ad_hoc_cov(info) # just a stub for later
with pytest.raises(ValueError, match='pick_ori must be one of'):
make_lcmv(info, forward, data_cov, 0.05, noise_cov, pick_ori='bad')
lcmv_ori = list()
for ti in range(n_vertices):
this_evoked = evoked.copy().crop(evoked.times[ti], evoked.times[ti])
data_cov['data'] = (np.outer(this_evoked.data, this_evoked.data) +
noise_cov['data'])
vals = linalg.svdvals(data_cov['data'])
assert vals[0] / vals[-1] < 1e5 # not rank deficient
filters = make_lcmv(info, forward, data_cov, 0.05, noise_cov)
filters_vector = make_lcmv(info, forward, data_cov, 0.05, noise_cov,
pick_ori='vector')
stc = apply_lcmv(this_evoked, filters)
assert isinstance(stc, mne.SourceEstimate)
stc_vector = apply_lcmv(this_evoked, filters_vector)
assert isinstance(stc_vector, mne.VectorSourceEstimate)
assert_allclose(stc.data, stc_vector.magnitude().data)
# Check the orientation by pooling across some neighbors, as LCMV can
# have some "holes" at the points of interest
idx = np.where(cdist(forward['source_rr'], source_rr[[ti]]) < 0.02)[0]
lcmv_ori.append(np.mean(stc_vector.data[idx, :, 0], axis=0))
lcmv_ori[-1] /= np.linalg.norm(lcmv_ori[-1])
lcmv_angles = np.rad2deg(np.arccos(np.sum(lcmv_ori * source_nn, axis=-1)))
assert np.mean(lcmv_angles) < 55
kwargs = dict(subjects_dir=subjects_dir, hemi='split', smoothing_steps=4,
time_unit='s', initial_time=0.05, size=1200,
views=['lat', 'med'])
clim = dict(kind='value', pos_lims=[1e-9, 1e-8, 1e-7])
figs = [mlab.figure(1), mlab.figure(2), mlab.figure(3), mlab.figure(4)]
brain_gen = stc_gen.plot(clim=clim, figure=figs, **kwargs)
###############################################################################
# Simulate sensor-space signals
# -----------------------------
#
# Use the forward solution and add Gaussian noise to simulate sensor-space
# (evoked) data from the known source-space signals. The amount of noise is
# controlled by `evoked_snr` (higher values imply less noise).
#
evoked_gen = simulate_evoked(fwd, stc_gen, evoked.info, cov, evoked_snr,
tmin=0., tmax=1., random_state=seed)
# Map the simulated sensor-space data to source-space using the inverse
# operator.
stc_inv = apply_inverse(evoked_gen, inv_op, lambda2, method=method)
###############################################################################
# Plot the point-spread of corrupted signal
# -----------------------------------------
#
# Notice that after applying the forward- and inverse-operators to the known
# point sources that the point sources have spread across the source-space.
# This spread is due to the minimum norm solution so that the signal leaks to
# nearby vertices with similar orientations so that signal ends up crossing the
# sulci and gyri.
figs = [mlab.figure(5), mlab.figure(6), mlab.figure(7), mlab.figure(8)]
def test_dipole_fitting(tmpdir):
"""Test dipole fitting."""
amp = 100e-9
tempdir = str(tmpdir)
rng = np.random.RandomState(0)
fname_dtemp = op.join(tempdir, 'test.dip')
fname_sim = op.join(tempdir, 'test-ave.fif')
fwd = convert_forward_solution(read_forward_solution(fname_fwd),
surf_ori=False, force_fixed=True,
use_cps=True)
evoked = read_evokeds(fname_evo)[0]
cov = read_cov(fname_cov)
n_per_hemi = 5
vertices = [np.sort(rng.permutation(s['vertno'])[:n_per_hemi])
for s in fwd['src']]
nv = sum(len(v) for v in vertices)
stc = SourceEstimate(amp * np.eye(nv), vertices, 0, 0.001)
evoked = simulate_evoked(fwd, stc, evoked.info, cov, nave=evoked.nave,
random_state=rng)
# For speed, let's use a subset of channels (strange but works)
picks = np.sort(np.concatenate([
pick_types(evoked.info, meg=True, eeg=False)[::2],
pick_types(evoked.info, meg=False, eeg=True)[::2]]))
evoked.pick_channels([evoked.ch_names[p] for p in picks])
evoked.add_proj(make_eeg_average_ref_proj(evoked.info))
write_evokeds(fname_sim, evoked)
# Run MNE-C version
run_subprocess([
'mne_dipole_fit', '--meas', fname_sim, '--meg', '--eeg',
'--noise', fname_cov, '--dip', fname_dtemp,
'--mri', fname_fwd, '--reg', '0', '--tmin', '0',
])
dip_c = read_dipole(fname_dtemp)
# Run mne-python version
sphere = make_sphere_model(head_radius=0.1)
with pytest.warns(RuntimeWarning, match='projection'):
dip, residual = fit_dipole(evoked, cov, sphere, fname_fwd)
assert isinstance(residual, Evoked)
# Sanity check: do our residuals have less power than orig data?
data_rms = np.sqrt(np.sum(evoked.data ** 2, axis=0))
resi_rms = np.sqrt(np.sum(residual.data ** 2, axis=0))
assert (data_rms > resi_rms * 0.95).all(), \
'%s (factor: %s)' % ((data_rms / resi_rms).min(), 0.95)
# Compare to original points
transform_surface_to(fwd['src'][0], 'head', fwd['mri_head_t'])
transform_surface_to(fwd['src'][1], 'head', fwd['mri_head_t'])
assert fwd['src'][0]['coord_frame'] == FIFF.FIFFV_COORD_HEAD
src_rr = np.concatenate([s['rr'][v] for s, v in zip(fwd['src'], vertices)],
axis=0)
src_nn = np.concatenate([s['nn'][v] for s, v in zip(fwd['src'], vertices)],
axis=0)
# MNE-C skips the last "time" point :(
out = dip.crop(dip_c.times[0], dip_c.times[-1])
assert (dip is out)
src_rr, src_nn = src_rr[:-1], src_nn[:-1]
# check that we did about as well
corrs, dists, gc_dists, amp_errs, gofs = [], [], [], [], []
for d in (dip_c, dip):
new = d.pos
diffs = new - src_rr
corrs += [np.corrcoef(src_rr.ravel(), new.ravel())[0, 1]]
dists += [np.sqrt(np.mean(np.sum(diffs * diffs, axis=1)))]
gc_dists += [180 / np.pi * np.mean(np.arccos(np.sum(src_nn * d.ori,
axis=1)))]
amp_errs += [np.sqrt(np.mean((amp - d.amplitude) ** 2))]
gofs += [np.mean(d.gof)]
# XXX possibly some OpenBLAS numerical differences make
# things slightly worse for us
factor = 0.7
assert dists[0] / factor >= dists[1], 'dists: %s' % dists
assert corrs[0] * factor <= corrs[1], 'corrs: %s' % corrs
assert gc_dists[0] / factor >= gc_dists[1] * 0.8, \
'gc-dists (ori): %s' % gc_dists
assert amp_errs[0] / factor >= amp_errs[1],\
'amplitude errors: %s' % amp_errs
# This one is weird because our cov/sim/picking is weird
assert gofs[0] * factor <= gofs[1] * 2, 'gof: %s' % gofs
def test_lcmv_vector():
"""Test vector LCMV solutions."""
info = mne.io.read_raw_fif(fname_raw).info
# For speed and for rank-deficiency calculation simplicity,
# just use grads
info = mne.pick_info(info, mne.pick_types(info, meg='grad', exclude=()))
info.update(bads=[], projs=[])
forward = mne.read_forward_solution(fname_fwd)
forward = mne.pick_channels_forward(forward, info['ch_names'])
vertices = [s['vertno'][::100] for s in forward['src']]
n_vertices = sum(len(v) for v in vertices)
assert 5 < n_vertices < 20
amplitude = 100e-9
stc = mne.SourceEstimate(amplitude * np.eye(n_vertices), vertices, 0,
1. / info['sfreq'])
forward_sim = mne.convert_forward_solution(forward,
force_fixed=True,
use_cps=True,
copy=True)
forward_sim = mne.forward.restrict_forward_to_stc(forward_sim, stc)
noise_cov = mne.make_ad_hoc_cov(info)
noise_cov.update(data=np.diag(noise_cov['data']), diag=False)
evoked = simulate_evoked(forward_sim, stc, info, noise_cov, nave=1)
source_nn = forward_sim['source_nn']
source_rr = forward_sim['source_rr']
# Figure out our indices
mask = np.concatenate(
[np.in1d(s['vertno'], v) for s, v in zip(forward['src'], vertices)])
mapping = np.where(mask)[0]
assert_array_equal(source_rr, forward['source_rr'][mapping])
# Don't check NN because we didn't rotate to surf ori
del forward_sim
# Let's do minimum norm as a sanity check (dipole_fit is slower)
inv = make_inverse_operator(info, forward, noise_cov, loose=1.)
stc_vector_mne = apply_inverse(evoked, inv, pick_ori='vector')
mne_ori = stc_vector_mne.data[mapping, :, np.arange(n_vertices)]
mne_ori /= np.linalg.norm(mne_ori, axis=-1)[:, np.newaxis]
mne_angles = np.rad2deg(np.arccos(np.sum(mne_ori * source_nn, axis=-1)))
assert np.mean(mne_angles) < 35
# Now let's do LCMV
data_cov = mne.make_ad_hoc_cov(info) # just a stub for later
with pytest.raises(ValueError, match="pick_ori"):
make_lcmv(info, forward, data_cov, 0.05, noise_cov, pick_ori='bad')
lcmv_ori = list()
for ti in range(n_vertices):
this_evoked = evoked.copy().crop(evoked.times[ti], evoked.times[ti])
data_cov['data'] = (np.outer(this_evoked.data, this_evoked.data) +
noise_cov['data'])
vals = linalg.svdvals(data_cov['data'])
assert vals[0] / vals[-1] < 1e5 # not rank deficient
with catch_logging() as log:
filters = make_lcmv(info,
forward,
data_cov,
0.05,
noise_cov,
verbose=True)
log = log.getvalue()
assert '498 sources' in log
with catch_logging() as log:
filters_vector = make_lcmv(info,
forward,
data_cov,
0.05,
noise_cov,
pick_ori='vector',
verbose=True)
log = log.getvalue()
assert '498 sources' in log
stc = apply_lcmv(this_evoked, filters)
stc_vector = apply_lcmv(this_evoked, filters_vector)
assert isinstance(stc, mne.SourceEstimate)
assert isinstance(stc_vector, mne.VectorSourceEstimate)
assert_allclose(stc.data, stc_vector.magnitude().data)
# Check the orientation by pooling across some neighbors, as LCMV can
# have some "holes" at the points of interest
idx = np.where(cdist(forward['source_rr'], source_rr[[ti]]) < 0.02)[0]
lcmv_ori.append(np.mean(stc_vector.data[idx, :, 0], axis=0))
lcmv_ori[-1] /= np.linalg.norm(lcmv_ori[-1])
lcmv_angles = np.rad2deg(np.arccos(np.sum(lcmv_ori * source_nn, axis=-1)))
assert np.mean(lcmv_angles) < 55
def test_dipole_fitting():
"""Test dipole fitting."""
amp = 10e-9
tempdir = _TempDir()
rng = np.random.RandomState(0)
fname_dtemp = op.join(tempdir, 'test.dip')
fname_sim = op.join(tempdir, 'test-ave.fif')
fwd = convert_forward_solution(read_forward_solution(fname_fwd),
surf_ori=False, force_fixed=True)
evoked = read_evokeds(fname_evo)[0]
cov = read_cov(fname_cov)
n_per_hemi = 5
vertices = [np.sort(rng.permutation(s['vertno'])[:n_per_hemi])
for s in fwd['src']]
nv = sum(len(v) for v in vertices)
stc = SourceEstimate(amp * np.eye(nv), vertices, 0, 0.001)
evoked = simulate_evoked(fwd, stc, evoked.info, cov, snr=20,
random_state=rng)
# For speed, let's use a subset of channels (strange but works)
picks = np.sort(np.concatenate([
pick_types(evoked.info, meg=True, eeg=False)[::2],
pick_types(evoked.info, meg=False, eeg=True)[::2]]))
evoked.pick_channels([evoked.ch_names[p] for p in picks])
evoked.add_proj(make_eeg_average_ref_proj(evoked.info))
write_evokeds(fname_sim, evoked)
# Run MNE-C version
run_subprocess([
'mne_dipole_fit', '--meas', fname_sim, '--meg', '--eeg',
'--noise', fname_cov, '--dip', fname_dtemp,
'--mri', fname_fwd, '--reg', '0', '--tmin', '0',
])
dip_c = read_dipole(fname_dtemp)
# Run mne-python version
sphere = make_sphere_model(head_radius=0.1)
dip, residuals = fit_dipole(evoked, fname_cov, sphere, fname_fwd)
# Sanity check: do our residuals have less power than orig data?
data_rms = np.sqrt(np.sum(evoked.data ** 2, axis=0))
resi_rms = np.sqrt(np.sum(residuals ** 2, axis=0))
factor = 1.
# XXX weird, inexplicable differenc for 3.5 build we'll assume is due to
# Anaconda bug for now...
if os.getenv('TRAVIS', 'false') == 'true' and \
sys.version[:3] in ('3.5', '2.7'):
factor = 0.8
assert_true((data_rms > factor * resi_rms).all(),
msg='%s (factor: %s)' % ((data_rms / resi_rms).min(), factor))
# Compare to original points
transform_surface_to(fwd['src'][0], 'head', fwd['mri_head_t'])
transform_surface_to(fwd['src'][1], 'head', fwd['mri_head_t'])
src_rr = np.concatenate([s['rr'][v] for s, v in zip(fwd['src'], vertices)],
axis=0)
src_nn = np.concatenate([s['nn'][v] for s, v in zip(fwd['src'], vertices)],
axis=0)
# MNE-C skips the last "time" point :(
dip.crop(dip_c.times[0], dip_c.times[-1])
src_rr, src_nn = src_rr[:-1], src_nn[:-1]
# check that we did at least as well
corrs, dists, gc_dists, amp_errs, gofs = [], [], [], [], []
for d in (dip_c, dip):
new = d.pos
diffs = new - src_rr
corrs += [np.corrcoef(src_rr.ravel(), new.ravel())[0, 1]]
dists += [np.sqrt(np.mean(np.sum(diffs * diffs, axis=1)))]
gc_dists += [180 / np.pi * np.mean(np.arccos(np.sum(src_nn * d.ori,
axis=1)))]
amp_errs += [np.sqrt(np.mean((amp - d.amplitude) ** 2))]
gofs += [np.mean(d.gof)]
assert_true(dists[0] >= dists[1] * factor, 'dists: %s' % dists)
assert_true(corrs[0] <= corrs[1] / factor, 'corrs: %s' % corrs)
assert_true(gc_dists[0] >= gc_dists[1] * factor,
'gc-dists (ori): %s' % gc_dists)
assert_true(amp_errs[0] >= amp_errs[1] * factor,
'amplitude errors: %s' % amp_errs)
assert_true(gofs[0] <= gofs[1] / factor, 'gof: %s' % gofs)
def test_dipole_fitting():
"""Test dipole fitting"""
amp = 10e-9
tempdir = _TempDir()
rng = np.random.RandomState(0)
fname_dtemp = op.join(tempdir, "test.dip")
fname_sim = op.join(tempdir, "test-ave.fif")
fwd = convert_forward_solution(read_forward_solution(fname_fwd), surf_ori=False, force_fixed=True)
evoked = read_evokeds(fname_evo)[0]
cov = read_cov(fname_cov)
n_per_hemi = 5
vertices = [np.sort(rng.permutation(s["vertno"])[:n_per_hemi]) for s in fwd["src"]]
nv = sum(len(v) for v in vertices)
stc = SourceEstimate(amp * np.eye(nv), vertices, 0, 0.001)
evoked = simulate_evoked(fwd, stc, evoked.info, cov, snr=20, random_state=rng)
# For speed, let's use a subset of channels (strange but works)
picks = np.sort(
np.concatenate(
[pick_types(evoked.info, meg=True, eeg=False)[::2], pick_types(evoked.info, meg=False, eeg=True)[::2]]
)
)
evoked.pick_channels([evoked.ch_names[p] for p in picks])
evoked.add_proj(make_eeg_average_ref_proj(evoked.info))
write_evokeds(fname_sim, evoked)
# Run MNE-C version
run_subprocess(
[
"mne_dipole_fit",
"--meas",
fname_sim,
"--meg",
"--eeg",
"--noise",
fname_cov,
"--dip",
fname_dtemp,
"--mri",
fname_fwd,
"--reg",
"0",
"--tmin",
"0",
]
)
dip_c = read_dipole(fname_dtemp)
# Run mne-python version
sphere = make_sphere_model(head_radius=0.1)
dip, residuals = fit_dipole(evoked, fname_cov, sphere, fname_fwd)
# Sanity check: do our residuals have less power than orig data?
data_rms = np.sqrt(np.sum(evoked.data ** 2, axis=0))
resi_rms = np.sqrt(np.sum(residuals ** 2, axis=0))
assert_true((data_rms > resi_rms).all())
# Compare to original points
transform_surface_to(fwd["src"][0], "head", fwd["mri_head_t"])
transform_surface_to(fwd["src"][1], "head", fwd["mri_head_t"])
src_rr = np.concatenate([s["rr"][v] for s, v in zip(fwd["src"], vertices)], axis=0)
src_nn = np.concatenate([s["nn"][v] for s, v in zip(fwd["src"], vertices)], axis=0)
# MNE-C skips the last "time" point :(
dip.crop(dip_c.times[0], dip_c.times[-1])
src_rr, src_nn = src_rr[:-1], src_nn[:-1]
# check that we did at least as well
corrs, dists, gc_dists, amp_errs, gofs = [], [], [], [], []
for d in (dip_c, dip):
new = d.pos
diffs = new - src_rr
corrs += [np.corrcoef(src_rr.ravel(), new.ravel())[0, 1]]
dists += [np.sqrt(np.mean(np.sum(diffs * diffs, axis=1)))]
gc_dists += [180 / np.pi * np.mean(np.arccos(np.sum(src_nn * d.ori, axis=1)))]
amp_errs += [np.sqrt(np.mean((amp - d.amplitude) ** 2))]
gofs += [np.mean(d.gof)]
assert_true(dists[0] >= dists[1], "dists: %s" % dists)
assert_true(corrs[0] <= corrs[1], "corrs: %s" % corrs)
assert_true(gc_dists[0] >= gc_dists[1], "gc-dists (ori): %s" % gc_dists)
assert_true(amp_errs[0] >= amp_errs[1], "amplitude errors: %s" % amp_errs)
assert_true(gofs[0] <= gofs[1], "gof: %s" % gofs)
size=1200,
views=['lat', 'med'])
clim = dict(kind='value', pos_lims=[1e-9, 1e-8, 1e-7])
brain_gen = stc_gen.plot(clim=clim, **kwargs)
###############################################################################
# Simulate sensor-space signals
# -----------------------------
#
# Use the forward solution and add Gaussian noise to simulate sensor-space
# (evoked) data from the known source-space signals. The amount of noise is
# controlled by `nave` (higher values imply less noise).
#
evoked_gen = simulate_evoked(fwd,
stc_gen,
evoked.info,
cov,
nave,
random_state=seed)
# Map the simulated sensor-space data to source-space using the inverse
# operator.
stc_inv = apply_inverse(evoked_gen, inv_op, lambda2, method=method)
###############################################################################
# Plot the point-spread of corrupted signal
# -----------------------------------------
#
# Notice that after applying the forward- and inverse-operators to the known
# point sources that the point sources have spread across the source-space.
# This spread is due to the minimum norm solution so that the signal leaks to
# nearby vertices with similar orientations so that signal ends up crossing the
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'])
with pytest.deprecated_call(match='full'): # this won't depend on rank
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)
# 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.
pytest.raises(ValueError,
simulate_evoked,
fwd,
stc,
evoked_template.info,
cov,
nave=nave,
iir_filter=None)
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]
nave = 100 # simulate average of 100 epochs
evoked = simulate_evoked(fwd,
stc,
info,
cov,
nave=nave,
use_cps=True,
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])
def test_make_forward_dipole():
"""Test forward-projecting dipoles"""
rng = np.random.RandomState(0)
evoked = read_evokeds(fname_evo)[0]
cov = read_cov(fname_cov)
dip_c = read_dipole(fname_dip)
# Only use magnetometers for speed!
picks = pick_types(evoked.info, meg='mag', eeg=False)
evoked.pick_channels([evoked.ch_names[p] for p in picks])
info = evoked.info
# Make new Dipole object with n_test_dipoles picked from the dipoles
# in the test dataset.
n_test_dipoles = 3 # minimum 3 needed to get uneven sampling in time
dipsel = np.sort(rng.permutation(np.arange(len(dip_c)))[:n_test_dipoles])
dip_test = Dipole(times=dip_c.times[dipsel],
pos=dip_c.pos[dipsel],
amplitude=dip_c.amplitude[dipsel],
ori=dip_c.ori[dipsel],
gof=dip_c.gof[dipsel])
sphere = make_sphere_model(head_radius=0.1)
# Warning emitted due to uneven sampling in time
with warnings.catch_warnings(record=True) as w:
fwd, stc = make_forward_dipole(dip_test,
sphere,
info,
trans=fname_trans)
assert_true(issubclass(w[-1].category, RuntimeWarning))
# stc is list of VolSourceEstimate's
assert_true(isinstance(stc, list))
for nd in range(n_test_dipoles):
assert_true(isinstance(stc[nd], VolSourceEstimate))
# Now simulate evoked responses for each of the test dipoles,
# and fit dipoles to them (sphere model, MEG and EEG)
times, pos, amplitude, ori, gof = [], [], [], [], []
snr = 20. # add a tiny amount of noise to the simulated evokeds
for s in stc:
evo_test = simulate_evoked(fwd,
s,
info,
cov,
snr=snr,
random_state=rng)
# evo_test.add_proj(make_eeg_average_ref_proj(evo_test.info))
dfit, resid = fit_dipole(evo_test, cov, sphere, None)
times += dfit.times.tolist()
pos += dfit.pos.tolist()
amplitude += dfit.amplitude.tolist()
ori += dfit.ori.tolist()
gof += dfit.gof.tolist()
# Create a new Dipole object with the dipole fits
dip_fit = Dipole(times, pos, amplitude, ori, gof)
# check that true (test) dipoles and fits are "close"
# cf. mne/tests/test_dipole.py
diff = dip_test.pos - dip_fit.pos
corr = np.corrcoef(dip_test.pos.ravel(), dip_fit.pos.ravel())[0, 1]
dist = np.sqrt(np.mean(np.sum(diff * diff, axis=1)))
gc_dist = 180 / np.pi * \
np.mean(np.arccos(np.sum(dip_test.ori * dip_fit.ori, axis=1)))
amp_err = np.sqrt(np.mean((dip_test.amplitude - dip_fit.amplitude)**2))
# Make sure each coordinate is close to reference
# NB tolerance should be set relative to snr of simulated evoked!
assert_allclose(dip_fit.pos,
dip_test.pos,
rtol=0,
atol=1e-2,
err_msg='position mismatch')
assert_true(dist < 1e-2, 'dist: %s' % dist) # within 1 cm
assert_true(corr > 1 - 1e-2, 'corr: %s' % corr)
assert_true(gc_dist < 20, 'gc_dist: %s' % gc_dist) # less than 20 degrees
assert_true(amp_err < 10e-9, 'amp_err: %s' % amp_err) # within 10 nAm
# Make sure rejection works with BEM: one dipole at z=1m
# NB _make_forward.py:_prepare_for_forward will raise a RuntimeError
# if no points are left after min_dist exclusions, hence 2 dips here!
dip_outside = Dipole(times=[0., 0.001],
pos=[[0., 0., 1.0], [0., 0., 0.040]],
amplitude=[100e-9, 100e-9],
ori=[[1., 0., 0.], [1., 0., 0.]],
gof=1)
assert_raises(ValueError, make_forward_dipole, dip_outside, fname_bem,
info, fname_trans)
# if we get this far, can safely assume the code works with BEMs too
# -> use sphere again below for speed
# Now make an evenly sampled set of dipoles, some simultaneous,
# should return a VolSourceEstimate regardless
times = [0., 0., 0., 0.001, 0.001, 0.002]
pos = np.random.rand(6, 3) * 0.020 + \
np.array([0., 0., 0.040])[np.newaxis, :]
amplitude = np.random.rand(6) * 100e-9
ori = np.eye(6, 3) + np.eye(6, 3, -3)
gof = np.arange(len(times)) / len(times) # arbitrary
dip_even_samp = Dipole(times, pos, amplitude, ori, gof)
fwd, stc = make_forward_dipole(dip_even_samp,
sphere,
info,
trans=fname_trans)
assert_true(isinstance, VolSourceEstimate)
assert_allclose(stc.times, np.arange(0., 0.003, 0.001))
def test_make_forward_dipole():
"""Test forward-projecting dipoles."""
rng = np.random.RandomState(0)
evoked = read_evokeds(fname_evo)[0]
cov = read_cov(fname_cov)
cov['projs'] = [] # avoid proj warning
dip_c = read_dipole(fname_dip)
# Only use magnetometers for speed!
picks = pick_types(evoked.info, meg='mag', eeg=False)[::8]
evoked.pick_channels([evoked.ch_names[p] for p in picks])
evoked.info.normalize_proj()
info = evoked.info
# Make new Dipole object with n_test_dipoles picked from the dipoles
# in the test dataset.
n_test_dipoles = 3 # minimum 3 needed to get uneven sampling in time
dipsel = np.sort(rng.permutation(np.arange(len(dip_c)))[:n_test_dipoles])
dip_test = Dipole(times=dip_c.times[dipsel],
pos=dip_c.pos[dipsel],
amplitude=dip_c.amplitude[dipsel],
ori=dip_c.ori[dipsel],
gof=dip_c.gof[dipsel])
sphere = make_sphere_model(head_radius=0.1)
# Warning emitted due to uneven sampling in time
with pytest.warns(RuntimeWarning, match='unevenly spaced'):
fwd, stc = make_forward_dipole(dip_test, sphere, info,
trans=fname_trans)
# stc is list of VolSourceEstimate's
assert isinstance(stc, list)
for n_dip in range(n_test_dipoles):
assert isinstance(stc[n_dip], VolSourceEstimate)
# Now simulate evoked responses for each of the test dipoles,
# and fit dipoles to them (sphere model, MEG and EEG)
times, pos, amplitude, ori, gof = [], [], [], [], []
nave = 200 # add a tiny amount of noise to the simulated evokeds
for s in stc:
evo_test = simulate_evoked(fwd, s, info, cov,
nave=nave, random_state=rng)
# evo_test.add_proj(make_eeg_average_ref_proj(evo_test.info))
dfit, resid = fit_dipole(evo_test, cov, sphere, None)
times += dfit.times.tolist()
pos += dfit.pos.tolist()
amplitude += dfit.amplitude.tolist()
ori += dfit.ori.tolist()
gof += dfit.gof.tolist()
# Create a new Dipole object with the dipole fits
dip_fit = Dipole(times, pos, amplitude, ori, gof)
# check that true (test) dipoles and fits are "close"
# cf. mne/tests/test_dipole.py
diff = dip_test.pos - dip_fit.pos
corr = np.corrcoef(dip_test.pos.ravel(), dip_fit.pos.ravel())[0, 1]
dist = np.sqrt(np.mean(np.sum(diff * diff, axis=1)))
gc_dist = 180 / np.pi * \
np.mean(np.arccos(np.sum(dip_test.ori * dip_fit.ori, axis=1)))
amp_err = np.sqrt(np.mean((dip_test.amplitude - dip_fit.amplitude) ** 2))
# Make sure each coordinate is close to reference
# NB tolerance should be set relative to snr of simulated evoked!
assert_allclose(dip_fit.pos, dip_test.pos, rtol=0, atol=1e-2,
err_msg='position mismatch')
assert dist < 1e-2 # within 1 cm
assert corr > 0.985
assert gc_dist < 20 # less than 20 degrees
assert amp_err < 10e-9 # within 10 nAm
# Make sure rejection works with BEM: one dipole at z=1m
# NB _make_forward.py:_prepare_for_forward will raise a RuntimeError
# if no points are left after min_dist exclusions, hence 2 dips here!
dip_outside = Dipole(times=[0., 0.001],
pos=[[0., 0., 1.0], [0., 0., 0.040]],
amplitude=[100e-9, 100e-9],
ori=[[1., 0., 0.], [1., 0., 0.]], gof=1)
pytest.raises(ValueError, make_forward_dipole, dip_outside, fname_bem,
info, fname_trans)
# if we get this far, can safely assume the code works with BEMs too
# -> use sphere again below for speed
# Now make an evenly sampled set of dipoles, some simultaneous,
# should return a VolSourceEstimate regardless
times = [0., 0., 0., 0.001, 0.001, 0.002]
pos = np.random.rand(6, 3) * 0.020 + \
np.array([0., 0., 0.040])[np.newaxis, :]
amplitude = np.random.rand(6) * 100e-9
ori = np.eye(6, 3) + np.eye(6, 3, -3)
gof = np.arange(len(times)) / len(times) # arbitrary
dip_even_samp = Dipole(times, pos, amplitude, ori, gof)
fwd, stc = make_forward_dipole(dip_even_samp, sphere, info,
trans=fname_trans)
assert isinstance(stc, VolSourceEstimate)
assert_allclose(stc.times, np.arange(0., 0.003, 0.001))
def test_dipole_fitting():
"""Test dipole fitting."""
amp = 100e-9
tempdir = _TempDir()
rng = np.random.RandomState(0)
fname_dtemp = op.join(tempdir, 'test.dip')
fname_sim = op.join(tempdir, 'test-ave.fif')
fwd = convert_forward_solution(read_forward_solution(fname_fwd),
surf_ori=False, force_fixed=True,
use_cps=True)
evoked = read_evokeds(fname_evo)[0]
cov = read_cov(fname_cov)
n_per_hemi = 5
vertices = [np.sort(rng.permutation(s['vertno'])[:n_per_hemi])
for s in fwd['src']]
nv = sum(len(v) for v in vertices)
stc = SourceEstimate(amp * np.eye(nv), vertices, 0, 0.001)
evoked = simulate_evoked(fwd, stc, evoked.info, cov, nave=evoked.nave,
random_state=rng)
# For speed, let's use a subset of channels (strange but works)
picks = np.sort(np.concatenate([
pick_types(evoked.info, meg=True, eeg=False)[::2],
pick_types(evoked.info, meg=False, eeg=True)[::2]]))
evoked.pick_channels([evoked.ch_names[p] for p in picks])
evoked.add_proj(make_eeg_average_ref_proj(evoked.info))
write_evokeds(fname_sim, evoked)
# Run MNE-C version
run_subprocess([
'mne_dipole_fit', '--meas', fname_sim, '--meg', '--eeg',
'--noise', fname_cov, '--dip', fname_dtemp,
'--mri', fname_fwd, '--reg', '0', '--tmin', '0',
])
dip_c = read_dipole(fname_dtemp)
# Run mne-python version
sphere = make_sphere_model(head_radius=0.1)
with warnings.catch_warnings(record=True):
dip, residuals = fit_dipole(evoked, cov, sphere, fname_fwd)
# Sanity check: do our residuals have less power than orig data?
data_rms = np.sqrt(np.sum(evoked.data ** 2, axis=0))
resi_rms = np.sqrt(np.sum(residuals ** 2, axis=0))
assert_true((data_rms > resi_rms * 0.95).all(),
msg='%s (factor: %s)' % ((data_rms / resi_rms).min(), 0.95))
# Compare to original points
transform_surface_to(fwd['src'][0], 'head', fwd['mri_head_t'])
transform_surface_to(fwd['src'][1], 'head', fwd['mri_head_t'])
assert_equal(fwd['src'][0]['coord_frame'], FIFF.FIFFV_COORD_HEAD)
src_rr = np.concatenate([s['rr'][v] for s, v in zip(fwd['src'], vertices)],
axis=0)
src_nn = np.concatenate([s['nn'][v] for s, v in zip(fwd['src'], vertices)],
axis=0)
# MNE-C skips the last "time" point :(
out = dip.crop(dip_c.times[0], dip_c.times[-1])
assert_true(dip is out)
src_rr, src_nn = src_rr[:-1], src_nn[:-1]
# check that we did about as well
corrs, dists, gc_dists, amp_errs, gofs = [], [], [], [], []
for d in (dip_c, dip):
new = d.pos
diffs = new - src_rr
corrs += [np.corrcoef(src_rr.ravel(), new.ravel())[0, 1]]
dists += [np.sqrt(np.mean(np.sum(diffs * diffs, axis=1)))]
gc_dists += [180 / np.pi * np.mean(np.arccos(np.sum(src_nn * d.ori,
axis=1)))]
amp_errs += [np.sqrt(np.mean((amp - d.amplitude) ** 2))]
gofs += [np.mean(d.gof)]
factor = 0.8
assert_true(dists[0] / factor >= dists[1], 'dists: %s' % dists)
assert_true(corrs[0] * factor <= corrs[1], 'corrs: %s' % corrs)
assert_true(gc_dists[0] / factor >= gc_dists[1] * 0.8,
'gc-dists (ori): %s' % gc_dists)
assert_true(amp_errs[0] / factor >= amp_errs[1],
'amplitude errors: %s' % amp_errs)
# This one is weird because our cov/sim/picking is weird
assert_true(gofs[0] * factor <= gofs[1] * 2, 'gof: %s' % gofs)
# 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])
evoked.plot()
def test_simulate_evoked():
"""Test simulation of evoked data."""
raw = read_raw_fif(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'])
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)
