Description of the problem

Hi there,

I tried to run the tutorial Repairing artifacts with SSP with my own data.

I have problems with using function create_ecg_epochs, compute_proj_ecg.
I tried both EEG and MEG data, and the bug goes like:
"Produces a ValueError: Unable to generate artificial ECG channel"

I want to run ssp before ica, since ica is not enough for me to repair ecg/eog artifacts,
but I fail to compute the projections with SSP.
Any tips or hints will be appreciated - Thx!

Wentao

Steps to reproduce

The first is what I do for EEG

base = os.path.join(os.getcwd(), os.pardir, os.pardir)
path_data = os.path.join(base, "data", "eeg", "demo","005", "20221223")
path_eeg = os.path.join(path_data, "eeg", "image-audio-post.vhdr")
path_montage = os.path.join(path_data, "standard-1020-cap64.locs")
path_output = os.path.join(os.getcwd(), "output")

# Execute preprocess pipeline.
data = preprocess_session(path_eeg, path_montage, path_output)
data = mne.io.read_raw_brainvision(path_eeg, preload=True)
# Annotate channel types according to config.
data = init_channel_types(data, channel_types=config.channel_types)
# Update the locations of channels for future plot.
data = init_channel_montage(data, path_montage)
## Preprocess data.
# Remove bad channels from data.
data = remove_bad_channels(data, bad_channels=config.bad_channels)
# Set reference channels of data.
data = set_ref_channels(data, ref_channels=config.ref_channels)
# Filter parts of signals' spectrum.
data = filter_spectrum(data, band_frange=config.band_frange, notch_freqs=config.notch_freqs)
# SSP
rojs_ecg, events_ecg  = mne.preprocessing.compute_proj_ecg(data1,n_eeg = 2,reject=None)


The Second is what I do for MEG
base = os.path.join(os.getcwd(), os.pardir, os.pardir)
path_data = os.path.join(base, "data", "meg", "demo","001", "20230214")
path_meg = os.path.join(path_data, "meg", "FL2_TEST1.fif")
path_output = os.path.join(os.getcwd(), "output")

# Execute preprocess pipeline.
data = mne.io.read_raw_fif(path_meg, preload=True)
ecg_evoked = mne.preprocessing.create_ecg_epochs(data).average()

Link to data

No response

Expected results

Created an SSP operator (subspace dimension = 3)
3 projection items activated
Using data from preloaded Raw for 58 events and 61 original time points ...
0 bad epochs dropped
Adding projection: planar--0.200-0.400-PCA-01
Adding projection: axial--0.200-0.400-PCA-01
Adding projection: eeg--0.200-0.400-PCA-01

Actual results

Traceback (most recent call last):
File "F:\PKU2\Research2\Yunzhe_Liu\Code\eeg2label\preprocess\meg\session.py", line 71, in
data = preprocess_session(path_meg, path_output)
File "F:\PKU2\Research2\Yunzhe_Liu\Code\eeg2label\preprocess\meg\session.py", line 56, in preprocess_session
ecg_evoked = mne.preprocessing.create_ecg_epochs(data).average()
File "", line 12, in create_ecg_epochs
File "E:\Anaconda3\envs\tensorflow\lib\site-packages\mne\preprocessing\ecg.py", line 346, in create_ecg_epochs
events, _, _, ecg = find_ecg_events(
File "", line 12, in find_ecg_events
File "E:\Anaconda3\envs\tensorflow\lib\site-packages\mne\preprocessing\ecg.py", line 194, in find_ecg_events
ecg, _ = _make_ecg(raw, start=None, stop=None)
File "", line 12, in _make_ecg
File "E:\Anaconda3\envs\tensorflow\lib\site-packages\mne\preprocessing\ecg.py", line 383, in _make_ecg
raise ValueError('Unable to generate artificial ECG channel')
ValueError: Unable to generate artificial ECG channel

Additional information

Platform: Windows-10-10.0.19044-SP0
Python: 3.9.13 (main, Oct 13 2022, 21:23:06) [MSC v.1916 64 bit (AMD64)]
Executable: E:\Anaconda3\envs\tensorflow\python.exe
CPU: AMD64 Family 23 Model 96 Stepping 1, AuthenticAMD: 12 cores
Memory: 15.4 GB

mne: 1.3.0
numpy: 1.24.1 {MKL 2022.1-Product with 6 threads}
scipy: 1.10.0
matplotlib: 3.6.3 {backend=QtAgg}

sklearn: 1.2.0
numba: Not found
nibabel: 5.0.0
nilearn: 0.10.0
dipy: 1.6.0
openmeeg: Not found
cupy: Not found
pandas: 1.5.2
pyvista: 0.37.0 {OpenGL could not be initialized}
pyvistaqt: 0.9.0
ipyvtklink: 0.2.3
vtk: Not found
qtpy: 2.3.0 {PyQt5=5.15.2}
ipympl: Not found
pyqtgraph: 0.13.1
pooch: v1.6.0

mne_bids: Not found
mne_nirs: Not found
mne_features: Not found
mne_qt_browser: 0.4.0
mne_connectivity: Not found
mne_icalabel: 0.4