def plot_ica_overlay_evoked(evoked, evoked_cln, title, show):
"""
workaround for https://github.com/mne-tools/mne-python/issues/1819
copied from mne.viz.ica._plot_ica_overlay_evoked()
Plot evoked after and before ICA cleaning
Parameters
----------
ica : instance of mne.preprocessing.ICA
The ICA object.
epochs : instance of mne.Epochs
The Epochs to be regarded.
show : bool
If True, all open plots will be shown.
Returns
-------
fig : instance of pyplot.Figure
"""
ch_types_used = [c for c in ['mag', 'grad', 'eeg'] if c in evoked]
n_rows = len(ch_types_used)
ch_types_used_cln = [c for c in ['mag', 'grad', 'eeg'] if
c in evoked_cln]
if len(ch_types_used) != len(ch_types_used_cln):
raise ValueError('Raw and clean evokeds must match. '
'Found different channels.')
fig, axes = plt.subplots(n_rows, 1)
fig.suptitle('Average signal before (red) and after (black) ICA')
axes = axes.flatten() if isinstance(axes, np.ndarray) else axes
evoked.plot(axes=axes, show=False)
for ax in fig.axes:
[l.set_color('r') for l in ax.get_lines()]
fig.canvas.draw()
evoked_cln.plot(axes=axes, show=show)
tight_layout(fig=fig)
if show:
plt.show()
fig.subplots_adjust(top=0.90)
fig.canvas.draw()
def plot_ica_overlay_evoked(evoked, evoked_cln, title, show):
"""
workaround for https://github.com/mne-tools/mne-python/issues/1819
copied from mne.viz.ica._plot_ica_overlay_evoked()
Plot evoked after and before ICA cleaning
Parameters
----------
ica : instance of mne.preprocessing.ICA
The ICA object.
epochs : instance of mne.Epochs
The Epochs to be regarded.
show : bool
If True, all open plots will be shown.
Returns
-------
fig : instance of pyplot.Figure
"""
ch_types_used = [c for c in ['mag', 'grad', 'eeg'] if c in evoked]
n_rows = len(ch_types_used)
ch_types_used_cln = [c for c in ['mag', 'grad', 'eeg'] if
c in evoked_cln]
if len(ch_types_used) != len(ch_types_used_cln):
raise ValueError('Raw and clean evokeds must match. '
'Found different channels.')
fig, axes = plt.subplots(n_rows, 1)
fig.suptitle('Average signal before (red) and after (black) ICA')
axes = axes.flatten() if isinstance(axes, np.ndarray) else axes
evoked.plot(axes=axes, show=False)
for ax in fig.axes:
[l.set_color('r') for l in ax.get_lines()]
fig.canvas.draw()
evoked_cln.plot(axes=axes, show=show)
tight_layout(fig=fig)
if show:
plt.show()
fig.subplots_adjust(top=0.90)
fig.canvas.draw()
def _plot_evoked(evoked, plot_type, colorbar=True, hline=None, ylim=None,
picks=None, exclude='bads', unit=True, show=True,
clim=None, proj=False, xlim='tight', units=None,
scalings=None, titles=None, axes=None, cmap='RdBu_r'):
"""Aux function for plot_evoked and plot_evoked_image (cf. docstrings)
Extra param is:
plot_type : str, value ('butterfly' | 'image')
The type of graph to plot: 'butterfly' plots each channel as a line
(x axis: time, y axis: amplitude). 'image' plots a 2D image where
color depicts the amplitude of each channel at a given time point
(x axis: time, y axis: channel). In 'image' mode, the plot is not
interactive.
"""
import matplotlib.pyplot as plt
if axes is not None and proj == 'interactive':
raise RuntimeError('Currently only single axis figures are supported'
' for interactive SSP selection.')
scalings = _handle_default('scalings', scalings)
titles = _handle_default('titles', titles)
units = _handle_default('units', units)
channel_types = set(key for d in [scalings, titles, units] for key in d)
channel_types = sorted(channel_types) # to guarantee consistent order
if picks is None:
picks = list(range(evoked.info['nchan']))
bad_ch_idx = [evoked.ch_names.index(ch) for ch in evoked.info['bads']
if ch in evoked.ch_names]
if len(exclude) > 0:
if isinstance(exclude, string_types) and exclude == 'bads':
exclude = bad_ch_idx
elif (isinstance(exclude, list)
and all([isinstance(ch, string_types) for ch in exclude])):
exclude = [evoked.ch_names.index(ch) for ch in exclude]
else:
raise ValueError('exclude has to be a list of channel names or '
'"bads"')
picks = list(set(picks).difference(exclude))
types = [channel_type(evoked.info, idx) for idx in picks]
n_channel_types = 0
ch_types_used = []
for t in channel_types:
if t in types:
n_channel_types += 1
ch_types_used.append(t)
axes_init = axes # remember if axes where given as input
fig = None
if axes is None:
fig, axes = plt.subplots(n_channel_types, 1)
if isinstance(axes, plt.Axes):
axes = [axes]
elif isinstance(axes, np.ndarray):
axes = list(axes)
if axes_init is not None:
fig = axes[0].get_figure()
if not len(axes) == n_channel_types:
raise ValueError('Number of axes (%g) must match number of channel '
'types (%g)' % (len(axes), n_channel_types))
# instead of projecting during each iteration let's use the mixin here.
if proj is True and evoked.proj is not True:
evoked = evoked.copy()
evoked.apply_proj()
times = 1e3 * evoked.times # time in miliseconds
for ax, t in zip(axes, ch_types_used):
ch_unit = units[t]
this_scaling = scalings[t]
if unit is False:
this_scaling = 1.0
ch_unit = 'NA' # no unit
idx = [picks[i] for i in range(len(picks)) if types[i] == t]
if len(idx) > 0:
# Parameters for butterfly interactive plots
if plot_type == 'butterfly':
if any([i in bad_ch_idx for i in idx]):
colors = ['k'] * len(idx)
for i in bad_ch_idx:
if i in idx:
colors[idx.index(i)] = 'r'
ax._get_lines.color_cycle = iter(colors)
else:
ax._get_lines.color_cycle = cycle(['k'])
# Set amplitude scaling
D = this_scaling * evoked.data[idx, :]
# plt.axes(ax)
if plot_type == 'butterfly':
ax.plot(times, D.T)
elif plot_type == 'image':
im = ax.imshow(D, interpolation='nearest', origin='lower',
extent=[times[0], times[-1], 0, D.shape[0]],
aspect='auto', cmap=cmap)
if colorbar:
cbar = plt.colorbar(im, ax=ax)
cbar.ax.set_title(ch_unit)
elif plot_type == 'mean' :
# ax.plot(times, D.mean(axis=0))
ax.plot(times, np.abs(D).mean(axis=0))
if xlim is not None:
if xlim == 'tight':
xlim = (times[0], times[-1])
ax.set_xlim(xlim)
if ylim is not None and t in ylim:
if plot_type == 'butterfly' or plot_type == 'mean':
ax.set_ylim(ylim[t])
elif plot_type == 'image':
im.set_clim(ylim[t])
ax.set_title(titles[t] + ' (%d channel%s)' % (
len(D), 's' if len(D) > 1 else ''))
ax.set_xlabel('time (ms)')
if plot_type == 'butterfly' or plot_type == 'mean':
ax.set_ylabel('data (%s)' % ch_unit)
elif plot_type == 'image':
ax.set_ylabel('channels (%s)' % 'index')
else:
raise ValueError("plot_type has to be 'butterfly' or 'image'."
"Got %s." % plot_type)
if (plot_type == 'butterfly' or plot_type == 'mean') and (hline is not None):
for h in hline:
ax.axhline(h, color='r', linestyle='--', linewidth=2)
if axes_init is None:
plt.subplots_adjust(0.175, 0.08, 0.94, 0.94, 0.2, 0.63)
# if proj == 'interactive':
# _check_delayed_ssp(evoked)
# params = dict(evoked=evoked, fig=fig, projs=evoked.info['projs'],
# axes=axes, types=types, units=units, scalings=scalings,
# unit=unit, ch_types_used=ch_types_used, picks=picks,
# plot_update_proj_callback=_plot_update_evoked,
# plot_type=plot_type)
# _draw_proj_checkbox(None, params)
if show and plt.get_backend() != 'agg':
plt.show()
fig.canvas.draw() # for axes plots update axes.
tight_layout(fig=fig)
return fig
def plot_chpi_snr_raw(raw,
win_length,
n_harmonics=None,
show=True,
verbose=True):
"""Compute and plot cHPI SNR from raw data
Parameters
----------
win_length : float
Length of window to use for SNR estimates (seconds). A longer window
will naturally include more low frequency power, resulting in lower
SNR.
n_harmonics : int or None
Number of line frequency harmonics to include in the model. If None,
use all harmonics up to the MEG analog lowpass corner.
show : bool
Show figure if True.
Returns
-------
fig : instance of matplotlib.figure.Figure
cHPI SNR as function of time, residual variance.
Notes
-----
A general linear model including cHPI and line frequencies is fit into
each data window. The cHPI power obtained from the model is then divided
by the residual variance (variance of signal unexplained by the model) to
obtain the SNR.
The SNR may decrease either due to decrease of cHPI amplitudes (e.g.
head moving away from the helmet), or due to increase in the residual
variance. In case of broadband interference that overlaps with the cHPI
frequencies, the resulting decreased SNR accurately reflects the true
situation. However, increased narrowband interference outside the cHPI
and line frequencies would also cause an increase in the residual variance,
even though it wouldn't necessarily affect estimation of the cHPI
amplitudes. Thus, this method is intended for a rough overview of cHPI
signal quality. A more accurate picture of cHPI quality (at an increased
computational cost) can be obtained by examining the goodness-of-fit of
the cHPI coil fits.
"""
import matplotlib.pyplot as plt
from mne.chpi import _get_hpi_info
# plotting parameters
legend_fontsize = 6
title_fontsize = 10
tick_fontsize = 10
label_fontsize = 10
# get some info from fiff
sfreq = raw.info['sfreq']
linefreq = raw.info['line_freq']
if n_harmonics is not None:
linefreqs = (np.arange(n_harmonics + 1) + 1) * linefreq
else:
linefreqs = np.arange(linefreq, raw.info['lowpass'], linefreq)
buflen = int(win_length * sfreq)
if buflen <= 0:
raise ValueError('Window length should be >0')
cfreqs = _get_hpi_info(raw.info, verbose=False)[0]
if verbose:
print('Nominal cHPI frequencies: %s Hz' % cfreqs)
print('Sampling frequency: %s Hz' % sfreq)
print('Using line freqs: %s Hz' % linefreqs)
print('Using buffers of %s samples = %s seconds\n' %
(buflen, buflen / sfreq))
pick_meg = pick_types(raw.info, meg=True, exclude=[])
pick_mag = pick_types(raw.info, meg='mag', exclude=[])
pick_grad = pick_types(raw.info, meg='grad', exclude=[])
nchan = len(pick_meg)
# grad and mag indices into an array that already has meg channels only
pick_mag_ = np.in1d(pick_meg, pick_mag).nonzero()[0]
pick_grad_ = np.in1d(pick_meg, pick_grad).nonzero()[0]
# create general linear model for the data
t = np.arange(buflen) / float(sfreq)
model = np.empty((len(t), 2 + 2 * (len(linefreqs) + len(cfreqs))))
model[:, 0] = t
model[:, 1] = np.ones(t.shape)
# add sine and cosine term for each freq
allfreqs = np.concatenate([linefreqs, cfreqs])
model[:, 2::2] = np.cos(2 * np.pi * t[:, np.newaxis] * allfreqs)
model[:, 3::2] = np.sin(2 * np.pi * t[:, np.newaxis] * allfreqs)
inv_model = linalg.pinv(model)
# drop last buffer to avoid overrun
bufs = np.arange(0, raw.n_times, buflen)[:-1]
tvec = bufs / sfreq
snr_avg_grad = np.zeros([len(cfreqs), len(bufs)])
hpi_pow_grad = np.zeros([len(cfreqs), len(bufs)])
snr_avg_mag = np.zeros([len(cfreqs), len(bufs)])
resid_vars = np.zeros([nchan, len(bufs)])
for ind, buf0 in enumerate(bufs):
if verbose:
print('Buffer %s/%s' % (ind + 1, len(bufs)))
megbuf = raw[pick_meg, buf0:buf0 + buflen][0].T
coeffs = np.dot(inv_model, megbuf)
coeffs_hpi = coeffs[2 + 2 * len(linefreqs):]
resid_vars[:, ind] = np.var(megbuf - np.dot(model, coeffs), 0)
# get total power by combining sine and cosine terms
# sinusoidal of amplitude A has power of A**2/2
hpi_pow = (coeffs_hpi[0::2, :]**2 + coeffs_hpi[1::2, :]**2) / 2
hpi_pow_grad[:, ind] = hpi_pow[:, pick_grad_].mean(1)
# divide average HPI power by average variance
snr_avg_grad[:, ind] = hpi_pow_grad[:, ind] / \
resid_vars[pick_grad_, ind].mean()
snr_avg_mag[:, ind] = hpi_pow[:, pick_mag_].mean(1) / \
resid_vars[pick_mag_, ind].mean()
cfreqs_legend = ['%s Hz' % fre for fre in cfreqs]
fig, axs = plt.subplots(4, 1, sharex=True)
# SNR plots for gradiometers and magnetometers
ax = axs[0]
lines1 = ax.plot(tvec, 10 * np.log10(snr_avg_grad.T))
lines1_med = ax.plot(tvec,
10 * np.log10(np.median(snr_avg_grad, axis=0)),
lw=2,
ls=':',
color='k')
ax.set_xlim([tvec.min(), tvec.max()])
ax.set(ylabel='SNR (dB)')
ax.yaxis.label.set_fontsize(label_fontsize)
ax.set_title('Mean cHPI power / mean residual variance, gradiometers',
fontsize=title_fontsize)
ax.tick_params(axis='both', which='major', labelsize=tick_fontsize)
ax = axs[1]
lines2 = ax.plot(tvec, 10 * np.log10(snr_avg_mag.T))
lines2_med = ax.plot(tvec,
10 * np.log10(np.median(snr_avg_mag, axis=0)),
lw=2,
ls=':',
color='k')
ax.set_xlim([tvec.min(), tvec.max()])
ax.set(ylabel='SNR (dB)')
ax.yaxis.label.set_fontsize(label_fontsize)
ax.set_title('Mean cHPI power / mean residual variance, magnetometers',
fontsize=title_fontsize)
ax.tick_params(axis='both', which='major', labelsize=tick_fontsize)
ax = axs[2]
lines3 = ax.plot(tvec, hpi_pow_grad.T)
lines3_med = ax.plot(tvec,
np.median(hpi_pow_grad, axis=0),
lw=2,
ls=':',
color='k')
ax.set_xlim([tvec.min(), tvec.max()])
ax.set(ylabel='Power (T/m)$^2$')
ax.yaxis.label.set_fontsize(label_fontsize)
ax.set_title('Mean cHPI power, gradiometers', fontsize=title_fontsize)
ax.tick_params(axis='both', which='major', labelsize=tick_fontsize)
# residual (unexplained) variance as function of time
ax = axs[3]
cls = plt.get_cmap('plasma')(np.linspace(0., 0.7, len(pick_meg)))
ax.set_prop_cycle(color=cls)
ax.semilogy(tvec, resid_vars[pick_grad_, :].T, alpha=.4)
ax.set_xlim([tvec.min(), tvec.max()])
ax.set(ylabel='Var. (T/m)$^2$', xlabel='Time (s)')
ax.xaxis.label.set_fontsize(label_fontsize)
ax.yaxis.label.set_fontsize(label_fontsize)
ax.set_title('Residual (unexplained) variance, all gradiometer channels',
fontsize=title_fontsize)
ax.tick_params(axis='both', which='major', labelsize=tick_fontsize)
tight_layout(pad=.5, w_pad=.1, h_pad=.2) # from mne.viz
# tight_layout will screw these up
ax = axs[0]
box = ax.get_position()
ax.set_position([box.x0, box.y0, box.width * 0.8, box.height])
# order curve legends according to mean of data
sind = np.argsort(snr_avg_grad.mean(axis=1))[::-1]
handles = [lines1[i] for i in sind]
handles.append(lines1_med[0])
labels = [cfreqs_legend[i] for i in sind]
labels.append('Median')
leg_kwargs = dict(
prop={'size': legend_fontsize},
bbox_to_anchor=(
1.02,
0.5,
),
loc='center left',
borderpad=1,
handlelength=1,
)
ax.legend(handles, labels, **leg_kwargs)
ax = axs[1]
box = ax.get_position()
ax.set_position([box.x0, box.y0, box.width * 0.8, box.height])
sind = np.argsort(snr_avg_mag.mean(axis=1))[::-1]
handles = [lines2[i] for i in sind]
handles.append(lines2_med[0])
labels = [cfreqs_legend[i] for i in sind]
labels.append('Median')
ax.legend(handles, labels, **leg_kwargs)
ax = axs[2]
box = ax.get_position()
ax.set_position([box.x0, box.y0, box.width * 0.8, box.height])
sind = np.argsort(hpi_pow_grad.mean(axis=1))[::-1]
handles = [lines3[i] for i in sind]
handles.append(lines3_med[0])
labels = [cfreqs_legend[i] for i in sind]
labels.append('Median')
ax.legend(handles, labels, **leg_kwargs)
ax = axs[3]
box = ax.get_position()
ax.set_position([box.x0, box.y0, box.width * 0.8, box.height])
if show:
plt.show()
return fig
def _plot_evoked(evoked, plot_type, colorbar=True, hline=None, ylim=None,
picks=None, exclude='bads', unit=True, show=True,
clim=None, proj=False, xlim='tight', units=None,
scalings=None, titles=None, axes=None, cmap='RdBu_r'):
"""Aux function for plot_evoked and plot_evoked_image (cf. docstrings)
Extra param is:
plot_type : str, value ('butterfly' | 'image')
The type of graph to plot: 'butterfly' plots each channel as a line
(x axis: time, y axis: amplitude). 'image' plots a 2D image where
color depicts the amplitude of each channel at a given time point
(x axis: time, y axis: channel). In 'image' mode, the plot is not
interactive.
"""
import matplotlib.pyplot as plt
if axes is not None and proj == 'interactive':
raise RuntimeError('Currently only single axis figures are supported'
' for interactive SSP selection.')
scalings = _handle_default('scalings', scalings)
titles = _handle_default('titles', titles)
units = _handle_default('units', units)
channel_types = set(key for d in [scalings, titles, units] for key in d)
channel_types = sorted(channel_types) # to guarantee consistent order
if picks is None:
picks = list(range(evoked.info['nchan']))
bad_ch_idx = [evoked.ch_names.index(ch) for ch in evoked.info['bads']
if ch in evoked.ch_names]
if len(exclude) > 0:
if isinstance(exclude, string_types) and exclude == 'bads':
exclude = bad_ch_idx
elif (isinstance(exclude, list)
and all([isinstance(ch, string_types) for ch in exclude])):
exclude = [evoked.ch_names.index(ch) for ch in exclude]
else:
raise ValueError('exclude has to be a list of channel names or '
'"bads"')
picks = list(set(picks).difference(exclude))
types = [channel_type(evoked.info, idx) for idx in picks]
n_channel_types = 0
ch_types_used = []
for t in channel_types:
if t in types:
n_channel_types += 1
ch_types_used.append(t)
axes_init = axes # remember if axes where given as input
fig = None
if axes is None:
fig, axes = plt.subplots(n_channel_types, 1)
if isinstance(axes, plt.Axes):
axes = [axes]
elif isinstance(axes, np.ndarray):
axes = list(axes)
if axes_init is not None:
fig = axes[0].get_figure()
if not len(axes) == n_channel_types:
raise ValueError('Number of axes (%g) must match number of channel '
'types (%g)' % (len(axes), n_channel_types))
# instead of projecting during each iteration let's use the mixin here.
if proj is True and evoked.proj is not True:
evoked = evoked.copy()
evoked.apply_proj()
times = 1e3 * evoked.times # time in miliseconds
for ax, t in zip(axes, ch_types_used):
ch_unit = units[t]
this_scaling = scalings[t]
if unit is False:
this_scaling = 1.0
ch_unit = 'NA' # no unit
idx = [picks[i] for i in range(len(picks)) if types[i] == t]
if len(idx) > 0:
# Parameters for butterfly interactive plots
if plot_type == 'butterfly':
if any([i in bad_ch_idx for i in idx]):
colors = ['k'] * len(idx)
for i in bad_ch_idx:
if i in idx:
colors[idx.index(i)] = 'r'
ax._get_lines.color_cycle = iter(colors)
else:
ax._get_lines.color_cycle = cycle(['k'])
# Set amplitude scaling
D = this_scaling * evoked.data[idx, :]
# plt.axes(ax)
if plot_type == 'butterfly':
ax.plot(times, D.T)
elif plot_type == 'image':
im = ax.imshow(D, interpolation='nearest', origin='lower',
extent=[times[0], times[-1], 0, D.shape[0]],
aspect='auto', cmap=cmap)
if colorbar:
cbar = plt.colorbar(im, ax=ax)
cbar.ax.set_title(ch_unit)
elif plot_type == 'mean' :
# ax.plot(times, D.mean(axis=0))
ax.plot(times, np.abs(D).mean(axis=0))
if xlim is not None:
if xlim == 'tight':
xlim = (times[0], times[-1])
ax.set_xlim(xlim)
if ylim is not None and t in ylim:
if plot_type == 'butterfly' or plot_type == 'mean':
ax.set_ylim(ylim[t])
elif plot_type == 'image':
im.set_clim(ylim[t])
ax.set_title(titles[t] + ' (%d channel%s)' % (
len(D), 's' if len(D) > 1 else ''))
ax.set_xlabel('time (ms)')
if plot_type == 'butterfly' or plot_type == 'mean':
ax.set_ylabel('data (%s)' % ch_unit)
elif plot_type == 'image':
ax.set_ylabel('channels (%s)' % 'index')
else:
raise ValueError("plot_type has to be 'butterfly' or 'image'."
"Got %s." % plot_type)
if (plot_type == 'butterfly' or plot_type == 'mean') and (hline is not None):
for h in hline:
ax.axhline(h, color='r', linestyle='--', linewidth=2)
if axes_init is None:
plt.subplots_adjust(0.175, 0.08, 0.94, 0.94, 0.2, 0.63)
# if proj == 'interactive':
# _check_delayed_ssp(evoked)
# params = dict(evoked=evoked, fig=fig, projs=evoked.info['projs'],
# axes=axes, types=types, units=units, scalings=scalings,
# unit=unit, ch_types_used=ch_types_used, picks=picks,
# plot_update_proj_callback=_plot_update_evoked,
# plot_type=plot_type)
# _draw_proj_checkbox(None, params)
if show and plt.get_backend() != 'agg':
plt.show()
fig.canvas.draw() # for axes plots update axes.
tight_layout(fig=fig)
return fig
