def _cov_as_csd(cov, info):
rng = np.random.RandomState(0)
assert cov['data'].ndim == 2
assert len(cov['data']) == len(cov['names'])
# we need to make this have at least some complex structure
data = cov['data'] + 1e-1 * _rand_csd(rng, info)
assert data.dtype == np.complex128
return CrossSpectralDensity(_sym_mat_to_vector(data), cov['names'], 0., 16)
def _make_csd():
"""Make a simple CrossSpectralDensity object."""
frequencies = [1., 2., 3., 4.]
n_freqs = len(frequencies)
names = ['CH1', 'CH2', 'CH3']
tmin, tmax = (0., 1.)
data = np.arange(6. * n_freqs).reshape(n_freqs, 6).T
return CrossSpectralDensity(data, names, frequencies, 1, tmin, tmax)
def test_plot_csd():
"""Test plotting of CSD matrices."""
csd = CrossSpectralDensity([1, 2, 3], ['CH1', 'CH2'],
frequencies=[(10, 20)], n_fft=1,
tmin=0, tmax=1,)
plot_csd(csd, mode='csd') # Plot cross-spectral density
plot_csd(csd, mode='coh') # Plot coherence
plt.close('all')
def _make_rand_csd(info, csd):
rng = np.random.RandomState(0)
data = _rand_csd(rng, info)
# now we need to have the same null space as the data csd
s, u = np.linalg.eigh(csd.get_data(csd.frequencies[0]))
mask = np.abs(s) >= s[-1] * 1e-7
rank = mask.sum()
assert rank == len(data) == len(info['ch_names'])
noise_csd = CrossSpectralDensity(
_sym_mat_to_vector(data), info['ch_names'], 0., csd.n_fft)
return noise_csd, rank
def test_csd():
"""Test constructing a CrossSpectralDensity."""
csd = CrossSpectralDensity([1, 2, 3], ['CH1', 'CH2'], frequencies=1,
n_fft=1, tmin=0, tmax=1)
assert_array_equal(csd._data, [[1], [2], [3]]) # Conversion to 2D array
assert_array_equal(csd.frequencies, [1]) # Conversion to 1D array
# Channels don't match
raises(ValueError, CrossSpectralDensity, [1, 2, 3],
['CH1', 'CH2', 'Too many!'], tmin=0, tmax=1, frequencies=1, n_fft=1)
raises(ValueError, CrossSpectralDensity, [1, 2, 3], ['too little'],
tmin=0, tmax=1, frequencies=1, n_fft=1)
# Frequencies don't match
raises(ValueError, CrossSpectralDensity,
[[1, 2], [3, 4], [5, 6]], ['CH1', 'CH2'],
tmin=0, tmax=1, frequencies=1, n_fft=1)
# Invalid dims
raises(ValueError, CrossSpectralDensity, [[[1]]], ['CH1'], frequencies=1,
n_fft=1, tmin=0, tmax=1)
def test_make_dics(tmpdir, _load_forward, idx, whiten):
"""Test making DICS beamformer filters."""
# We only test proper handling of parameters here. Testing the results is
# done in test_apply_dics_timeseries and test_apply_dics_csd.
fwd_free, fwd_surf, fwd_fixed, fwd_vol = _load_forward
epochs, _, csd, _, label, vertices, source_ind = \
_simulate_data(fwd_fixed, idx)
with pytest.raises(ValueError, match='several sensor types'):
make_dics(epochs.info, fwd_surf, csd, label=label, pick_ori=None)
if whiten:
rng = np.random.RandomState(0)
scales = mne.make_ad_hoc_cov(epochs.info).data
n = scales.size
# Some random complex correlation structure (with channel scalings)
data = rng.randn(n, n) + 1j * rng.randn(n, n)
data = data @ data.conj().T
data *= scales
data *= scales[:, np.newaxis]
data.flat[::n + 1] = scales
noise_csd = CrossSpectralDensity(_sym_mat_to_vector(data),
epochs.ch_names, 0., csd.n_fft)
else:
noise_csd = None
epochs.pick_types(meg='grad')
with pytest.raises(ValueError, match="Invalid value for the 'pick_ori'"):
make_dics(epochs.info,
fwd_fixed,
csd,
pick_ori="notexistent",
noise_csd=noise_csd)
with pytest.raises(ValueError, match='rank, if str'):
make_dics(epochs.info, fwd_fixed, csd, rank='foo', noise_csd=noise_csd)
with pytest.raises(TypeError, match='rank must be'):
make_dics(epochs.info, fwd_fixed, csd, rank=1., noise_csd=noise_csd)
# Test if fixed forward operator is detected when picking normal
# orientation
with pytest.raises(ValueError, match='forward operator with free ori'):
make_dics(epochs.info,
fwd_fixed,
csd,
pick_ori="normal",
noise_csd=noise_csd)
# Test if non-surface oriented forward operator is detected when picking
# normal orientation
with pytest.raises(ValueError, match='oriented in surface coordinates'):
make_dics(epochs.info,
fwd_free,
csd,
pick_ori="normal",
noise_csd=noise_csd)
# Test if volume forward operator is detected when picking normal
# orientation
with pytest.raises(ValueError, match='oriented in surface coordinates'):
make_dics(epochs.info,
fwd_vol,
csd,
pick_ori="normal",
noise_csd=noise_csd)
# Test invalid combinations of parameters
with pytest.raises(ValueError, match='reduce_rank cannot be used with'):
make_dics(epochs.info,
fwd_free,
csd,
inversion='single',
reduce_rank=True,
noise_csd=noise_csd)
# TODO: Restore this?
# with pytest.raises(ValueError, match='not stable with depth'):
# make_dics(epochs.info, fwd_free, csd, weight_norm='unit-noise-gain',
# inversion='single', depth=None)
# Sanity checks on the returned filters
n_freq = len(csd.frequencies)
vertices = np.intersect1d(label.vertices, fwd_free['src'][0]['vertno'])
n_verts = len(vertices)
n_orient = 3
n_channels = len(epochs.ch_names)
# Test return values
weight_norm = 'unit-noise-gain'
inversion = 'single'
filters = make_dics(epochs.info,
fwd_surf,
csd,
label=label,
pick_ori=None,
weight_norm=weight_norm,
depth=None,
noise_csd=noise_csd,
inversion=inversion)
assert filters['weights'].shape == (n_freq, n_verts * n_orient, n_channels)
assert np.iscomplexobj(filters['weights'])
assert filters['csd'].ch_names == epochs.ch_names
assert isinstance(filters['csd'], CrossSpectralDensity)
assert filters['ch_names'] == epochs.ch_names
assert_array_equal(filters['proj'], np.eye(n_channels))
assert_array_equal(filters['vertices'][0], vertices)
assert_array_equal(filters['vertices'][1], []) # Label was on the LH
assert filters['subject'] == fwd_free['src']._subject
assert filters['pick_ori'] is None
assert filters['is_free_ori']
assert filters['inversion'] == inversion
assert filters['weight_norm'] == weight_norm
assert 'DICS' in repr(filters)
assert 'subject "sample"' in repr(filters)
assert str(len(vertices)) in repr(filters)
assert str(n_channels) in repr(filters)
assert 'rank' not in repr(filters)
_, noise_cov = _prepare_noise_csd(csd, noise_csd, real_filter=False)
_, _, _, _, G, _, _, _ = _prepare_beamformer_input(epochs.info,
fwd_surf,
label,
'vector',
combine_xyz=False,
exp=None,
noise_cov=noise_cov)
G.shape = (n_channels, n_verts, n_orient)
G = G.transpose(1, 2, 0).conj() # verts, orient, ch
_assert_weight_norm(filters, G)
inversion = 'matrix'
filters = make_dics(epochs.info,
fwd_surf,
csd,
label=label,
pick_ori=None,
weight_norm=weight_norm,
depth=None,
noise_csd=noise_csd,
inversion=inversion)
_assert_weight_norm(filters, G)
weight_norm = 'unit-noise-gain-invariant'
inversion = 'single'
filters = make_dics(epochs.info,
fwd_surf,
csd,
label=label,
pick_ori=None,
weight_norm=weight_norm,
depth=None,
noise_csd=noise_csd,
inversion=inversion)
_assert_weight_norm(filters, G)
# Test picking orientations. Also test weight norming under these different
# conditions.
weight_norm = 'unit-noise-gain'
filters = make_dics(epochs.info,
fwd_surf,
csd,
label=label,
pick_ori='normal',
weight_norm=weight_norm,
depth=None,
noise_csd=noise_csd,
inversion=inversion)
n_orient = 1
assert filters['weights'].shape == (n_freq, n_verts * n_orient, n_channels)
assert not filters['is_free_ori']
_assert_weight_norm(filters, G)
filters = make_dics(epochs.info,
fwd_surf,
csd,
label=label,
pick_ori='max-power',
weight_norm=weight_norm,
depth=None,
noise_csd=noise_csd,
inversion=inversion)
n_orient = 1
assert filters['weights'].shape == (n_freq, n_verts * n_orient, n_channels)
assert not filters['is_free_ori']
_assert_weight_norm(filters, G)
# From here on, only work on a single frequency
csd = csd[0]
# Test using a real-valued filter
filters = make_dics(epochs.info,
fwd_surf,
csd,
label=label,
pick_ori='normal',
real_filter=True,
noise_csd=noise_csd)
assert not np.iscomplexobj(filters['weights'])
# Test forward normalization. When inversion='single', the power of a
# unit-noise CSD should be 1, even without weight normalization.
if not whiten:
csd_noise = csd.copy()
inds = np.triu_indices(csd.n_channels)
# Using [:, :] syntax for in-place broadcasting
csd_noise._data[:, :] = np.eye(csd.n_channels)[inds][:, np.newaxis]
filters = make_dics(epochs.info,
fwd_surf,
csd_noise,
label=label,
weight_norm=None,
depth=1.,
noise_csd=noise_csd,
inversion='single')
w = filters['weights'][0][:3]
assert_allclose(np.diag(w.dot(w.conjugate().T)),
1.0,
rtol=1e-6,
atol=0)
# Test turning off both forward and weight normalization
filters = make_dics(epochs.info,
fwd_surf,
csd,
label=label,
weight_norm=None,
depth=None,
noise_csd=noise_csd)
w = filters['weights'][0][:3]
assert not np.allclose(
np.diag(w.dot(w.conjugate().T)), 1.0, rtol=1e-2, atol=0)
# Test neural-activity-index weight normalization. It should be a scaled
# version of the unit-noise-gain beamformer.
filters_nai = make_dics(epochs.info,
fwd_surf,
csd,
label=label,
pick_ori='max-power',
weight_norm='nai',
depth=None,
noise_csd=noise_csd)
w_nai = filters_nai['weights'][0]
filters_ung = make_dics(epochs.info,
fwd_surf,
csd,
label=label,
pick_ori='max-power',
weight_norm='unit-noise-gain',
depth=None,
noise_csd=noise_csd)
w_ung = filters_ung['weights'][0]
assert_allclose(np.corrcoef(np.abs(w_nai).ravel(),
np.abs(w_ung).ravel()),
1,
atol=1e-7)
# Test whether spatial filter contains src_type
assert 'src_type' in filters
fname = op.join(str(tmpdir), 'filters-dics.h5')
filters.save(fname)
filters_read = read_beamformer(fname)
assert isinstance(filters, Beamformer)
assert isinstance(filters_read, Beamformer)
for key in ['tmin', 'tmax']: # deal with strictness of object_diff
setattr(filters['csd'], key, np.float64(getattr(filters['csd'], key)))
assert object_diff(filters, filters_read) == ''