Prepare an empty-room recording for Maxwell filtering.
Empty-room data by default lacks certain properties that are required to
ensure running maxwell_filter() will process the
empty-room recording the same way as the experimental data. This function
preconditions an empty-room raw data instance accordingly so it can be used
for Maxwell filtering. Please see the Notes section for details.
RawThe empty-room recording. It will not be modified.
RawThe experimental recording, typically this will be the reference run used for Maxwell filtering.
How to populate the list of bad channel names to be injected into
the empty-room recording. If 'from_raw' (default) the list of bad
channels will be overwritten with that of raw. If 'union', will
use the union of bad channels in raw and raw_er. Note that
this may lead to additional bad channels in the empty-room in
comparison to the experimental recording. If 'keep', don’t alter
the existing list of bad channels.
Note
Non-MEG channels are silently dropped from the list of bads.
Whether to copy the annotations over from raw (default),
use the union of the annotations, or to keep them unchanged.
Whether to transfer the measurement date from raw or to keep
it as is (default). If you intend to manually transfer annotations
from raw after running this function, you should set this to
'from_raw'.
Whether to emit warnings when cropping or omitting annotations.
Unlike raw.set_annotations, the
default here is False, as empty-room recordings are often shorter
than raw.
str | int | NoneControl verbosity of the logging output. If None, use the default
verbosity level. See the logging documentation and
mne.verbose() for details. Should only be passed as a keyword
argument.
RawA copy of the passed empty-room recording, ready for Maxwell filtering.
Notes
This function will:
Compile the list of bad channels according to the bads parameter.
Inject the device-to-head transformation matrix from the experimental recording into the empty-room recording.
Set the following properties of the empty-room recording to match the experimental recording:
Montage
raw.first_time and raw.first_samp
Adjust annotations according to the annotations parameter.
Adjust the measurement date according to the meas_date parameter.
New in version 1.1.