BEM surface stats

bem_stats.py

# Author: Alexandre Gramfort <gramfort@nmr.mgh.harvard.edu>
#
# License: BSD (3-clause)

import numpy as np
from sklearn import neighbors
import mne
from mne.datasets import sample

data_path = sample.data_path()
fname = data_path + '/subjects/sample/bem/sample-5120-5120-5120-bem-sol.fif'

surfaces = mne.read_bem_surfaces(fname, add_geom=True)

print "Number of surfaces : %d" % len(surfaces)

for name, surf in zip(('head', 'skull', 'brain'), surfaces):
    points = surf['rr']
    nb = neighbors.NearestNeighbors(n_neighbors=2)
    nb.fit(points)
    G = nb.kneighbors(points, return_distance=True)
    print name, np.mean(G[0][:, 1])

output is:

head 0.00721512121192
skull 0.0057216261293
brain 0.00540786011339