mne.viz.plot_epochs

mne.viz.plot_epochs(epochs, picks=None, scalings=None, n_epochs=20, n_channels=20, title=None, events=None, event_colors=None, order=None, show=True, block=False, decim='auto', noise_cov=None, butterfly=False, show_scrollbars=True, epoch_colors=None, event_id=None)

Visualize epochs.

Bad epochs can be marked with a left click on top of the epoch. Bad channels can be selected by clicking the channel name on the left side of the main axes. Calling this function drops all the selected bad epochs as well as bad epochs marked beforehand with rejection parameters.

Parameters

epochsinstance of Epochs

The epochs object.

picksstr | list | slice | None

Channels to include. Slices and lists of integers will be interpreted as channel indices. In lists, channel type strings (e.g., ['meg', 'eeg']) will pick channels of those types, channel name strings (e.g., ['MEG0111', 'MEG2623'] will pick the given channels. Can also be the string values “all” to pick all channels, or “data” to pick data channels. None (default) will pick good data channels.

scalingsdict | ‘auto’ | None

Scaling factors for the traces. If any fields in scalings are ‘auto’, the scaling factor is set to match the 99.5th percentile of a subset of the corresponding data. If scalings == ‘auto’, all scalings fields are set to ‘auto’. If any fields are ‘auto’ and data is not preloaded, a subset of epochs up to 100mb will be loaded. If None, defaults to:

dict(mag=1e-12, grad=4e-11, eeg=20e-6, eog=150e-6, ecg=5e-4,
     emg=1e-3, ref_meg=1e-12, misc=1e-3, stim=1, resp=1, chpi=1e-4,
     whitened=10.)

n_epochsint

The number of epochs per view. Defaults to 20.

n_channelsint

The number of channels per view. Defaults to 20.

titlestr | None

The title of the window. If None, epochs name will be displayed. Defaults to None.

eventsNone, array, shape (n_events, 3)

Events to show with vertical bars. If events are provided, the epoch numbers are not shown to prevent overlap. You can toggle epoch numbering through options (press ‘o’ key). You can use plot_events as a legend for the colors. By default, the coloring scheme is the same.

Warning

If the epochs have been resampled, the events no longer align with the data.

New in version 0.14.0.

event_colorsNone, dict

Dictionary of event_id value and its associated color. If None, colors are automatically drawn from a default list (cycled through if number of events longer than list of default colors). Uses the same coloring scheme as plot_events.

New in version 0.14.0.

orderarray of str | None

Order in which to plot channel types.

New in version 0.18.0.

showbool

Show figure if True. Defaults to True.

blockbool

Whether to halt program execution until the figure is closed. Useful for rejecting bad trials on the fly by clicking on an epoch. Defaults to False.

decimint | ‘auto’

Amount to decimate the data during display for speed purposes. You should only decimate if the data are sufficiently low-passed, otherwise aliasing can occur. The ‘auto’ mode (default) uses the decimation that results in a sampling rate at least three times larger than info['lowpass'] (e.g., a 40 Hz lowpass will result in at least a 120 Hz displayed sample rate).

New in version 0.15.0.

noise_covinstance of Covariance | str | None

Noise covariance used to whiten the data while plotting. Whitened data channels are scaled by scalings['whitened'], and their channel names are shown in italic. Can be a string to load a covariance from disk. See also mne.Evoked.plot_white() for additional inspection of noise covariance properties when whitening evoked data. For data processed with SSS, the effective dependence between magnetometers and gradiometers may introduce differences in scaling, consider using mne.Evoked.plot_white().

New in version 0.16.0.

butterflybool

Whether to directly call the butterfly view.

New in version 0.18.0.

show_scrollbarsbool

Whether to show scrollbars when the plot is initialized. Can be toggled after initialization by pressing z (“zen mode”) while the plot window is focused. Default is True.

New in version 0.19.0.

epoch_colorslist of (n_epochs) list (of n_channels) | None

Colors to use for individual epochs. If None, use default colors.

event_iddict | None

Dictionary of event labels (e.g. ‘aud_l’) as keys and associated event integers as values. Useful when events contains event numbers not present in epochs.event_id (e.g., because of event subselection). Values in event_id will take precedence over those in epochs.event_id when there are overlapping keys.

New in version 0.20.

Returns

figinstance of matplotlib.figure.Figure

The figure.

Notes

The arrow keys (up/down/left/right) can be used to navigate between channels and epochs and the scaling can be adjusted with - and + (or =) keys, but this depends on the backend matplotlib is configured to use (e.g., mpl.use(TkAgg) should work). Full screen mode can be toggled with f11 key. The amount of epochs and channels per view can be adjusted with home/end and page down/page up keys. These can also be set through options dialog by pressing o key. h key plots a histogram of peak-to-peak values along with the used rejection thresholds. Butterfly plot can be toggled with b key. Right mouse click adds a vertical line to the plot. Click ‘help’ button at bottom left corner of the plotter to view all the options.

New in version 0.10.0.

Examples using mne.viz.plot_epochs