fwd_match.py

import mne
from mne.utils import object_diff
from mne.forward.forward import is_fixed_orient, convert_forward_solution
from mne.datasets import sample

data_path = sample.data_path()
fname_fwd = data_path + '/MEG/sample/sample_audvis-meg-oct-6-fwd.fif'
fname_inv = data_path + '/MEG/sample/sample_audvis-meg-oct-6-meg-inv.fif'
fwd = mne.read_forward_solution(fname_fwd)
inv = mne.minimum_norm.read_inverse_operator(fname_inv)


def _convert_forward_match_inv(fwd, inv):
    is_fixed_inv = inv['eigen_leads']['data'].shape[0] == inv['nsource']
    is_loose = not (inv['orient_prior'] == 1.).all()
    if is_fixed_inv:
        if not is_fixed_orient(fwd):
            fwd = convert_forward_solution(fwd, force_fixed=True)
    elif is_loose:
        if not fwd['surf_ori']:
            fwd = convert_forward_solution(fwd, surf_ori=True)
    else:  # free orientation
        if fwd['surf_ori']:
            fwd = convert_forward_solution(fwd, surf_ori=False)
    differences = object_diff(fwd['src'], inv['src'])
    if differences:
        raise RuntimeError('fwd["src"] and inv["src"] did not match: %s'
                           % (differences,))
    return fwd