Writing Fieldtrip epoch data into MNE format

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1

Hi team MNE,

I am new user of MNE python. I have a .fif file which is preprocessed in Fieldtrip (artifact rejection, ICA etc) and then i saved the data into a mat file having two main structures, data and cfg.

Now i want to process the data in MNE, when i try to write the mat file to fiff using functions fieldtrip2fiff it shows me that it cannot process the structures. I also tried with the functions of MNE matlab to write but it also shows me the same.

I shall be thankful if you guys can tell me how to read the epoched data from mat files in MNE.

Best regards
Sanjeev

Sanjeev Nara
Predoctoral Researcher BCBL
www.bcbl.eu
https://sites.google.com/view/sanjeev-nara/
Tel: +34 943 309 300 (ext 314)
Legal disclaimer/Aviso legal/Lege-oharra: www.bcbl.eu/legal-disclaimer

2

Hi Sanjeev,

You can convert fieldtrip data and cfg structure in to mne-python object
using Epoch class.

Please see sample code below, for more details see
https://martinos.org/mne/stable/generated/mne.Epochs.html

event_id = 1 # This is used to identify the events.
# First column is for the sample number.
events = np.array([[200, 0, event_id],
                   [1200, 0, event_id],
                   [2000, 0, event_id]]) # List of three arbitrary events

# Here a data set of 700 ms epochs from 2 channels is
# created from sin and cos data.
# Any data in shape (n_epochs, n_channels, n_times) can be used.
epochs_data = np.array([[sin[:700], cos[:700]],
                        [sin[1000:1700], cos[1000:1700]],
                        [sin[1800:2500], cos[1800:2500]]])

ch_names = ['sin', 'cos']
ch_types = ['mag', 'mag']
info = mne.create_info(ch_names=ch_names, sfreq=sfreq, ch_types=ch_types)

epochs = mne.EpochsArray(epochs_data, info=info, events=events,
                         event_id={'arbitrary': 1})

picks = mne.pick_types(info, meg=True, eeg=False, misc=False)

epochs.plot(picks=picks, scalings='auto', show=True, block=True)

HTH

Sheraz