mne.compute_proj_evoked

mne.compute_proj_evoked(evoked, n_grad=2, n_mag=2, n_eeg=2, desc_prefix=None, meg='separate', verbose=None)[source]

Compute SSP (signal-space projection) vectors on evoked data.

This function aims to find those SSP vectors that will project out the n most prominent signals from the data for each specified sensor type. Consequently, if the provided input data contains high levels of noise, the produced SSP vectors can then be used to eliminate that noise from the data.

Parameters
evokedinstance of Evoked

The Evoked obtained by averaging the artifact.

n_gradint

Number of vectors for gradiometers.

n_magint

Number of vectors for magnetometers.

n_eegint

Number of vectors for EEG channels.

desc_prefixstr | None

The description prefix to use. If None, one will be created based on tmin and tmax.

New in version 0.17.

megstr

Can be ‘separate’ (default) or ‘combined’ to compute projectors for magnetometers and gradiometers separately or jointly. If ‘combined’, n_mag == n_grad is required and the number of projectors computed for MEG will be n_mag.

New in version 0.18.

verbosebool, str, int, or None

If not None, override default verbose level (see mne.verbose() and Logging documentation for more). If used, it should be passed as a keyword-argument only.

Returns
projslist

List of projection vectors.