def test_topo_to_sph():
"""Test topo to sphere conversion."""
rng = np.random.RandomState(0)
angles = rng.rand(10) * 360
radii = rng.rand(10)
angles[0] = 30
radii[0] = 0.25
# new way
sph = _topo_to_sph(np.array([angles, radii]).T)
new = _sph_to_cart(sph)
new[:, [0, 1]] = new[:, [1, 0]] * [-1, 1]
# old way
for ii, (angle, radius) in enumerate(zip(angles, radii)):
sph_phi, sph_theta = _topo_to_sphere(angle, radius)
if ii == 0:
assert_allclose(_topo_to_sphere(angle, radius), [45, -30])
azimuth = sph_theta / 180.0 * np.pi
elevation = sph_phi / 180.0 * np.pi
assert_allclose(sph[ii], [1., azimuth, np.pi / 2. - elevation],
atol=1e-7)
r = np.ones_like(radius)
x, y, z = _sphere_to_cartesian(azimuth, elevation, r)
pos = [-y, x, z]
if ii == 0:
expected = np.array([1. / 2., np.sqrt(3) / 2., 1.])
expected /= np.sqrt(2)
assert_allclose(pos, expected, atol=1e-7)
assert_allclose(pos, new[ii], atol=1e-7)
def test_topo_to_sph():
"""Test topo to sphere conversion."""
rng = np.random.RandomState(0)
angles = rng.rand(10) * 360
radii = rng.rand(10)
angles[0] = 30
radii[0] = 0.25
# new way
sph = _topo_to_sph(np.array([angles, radii]).T)
new = _sph_to_cart(sph)
new[:, [0, 1]] = new[:, [1, 0]] * [-1, 1]
# old way
for ii, (angle, radius) in enumerate(zip(angles, radii)):
sph_phi, sph_theta = _topo_to_phi_theta(angle, radius)
if ii == 0:
assert_allclose(_topo_to_phi_theta(angle, radius), [45, -30])
azimuth = sph_theta / 180.0 * np.pi
elevation = sph_phi / 180.0 * np.pi
assert_allclose(sph[ii], [1., azimuth, np.pi / 2. - elevation],
atol=1e-7)
r = np.ones_like(radius)
x, y, z = _sphere_to_cartesian(azimuth, elevation, r)
pos = [-y, x, z]
if ii == 0:
expected = np.array([1. / 2., np.sqrt(3) / 2., 1.])
expected /= np.sqrt(2)
assert_allclose(pos, expected, atol=1e-7)
assert_allclose(pos, new[ii], atol=1e-7)
def _read_eeglab_montage(fname):
"""Read an EEGLAB digitization file.
Parameters
----------
fname : str
The filepath of Polhemus ISOTrak formatted file.
File extension is expected to be '.loc', '.locs' or '.eloc'.
Returns
-------
montage : instance of DigMontage
The montage.
See Also
--------
make_dig_montage
"""
ch_names = np.genfromtxt(fname, dtype=str, usecols=3).tolist()
topo = np.loadtxt(fname, dtype=float, usecols=[1, 2])
sph = _topo_to_sph(topo)
pos = _sph_to_cart(sph)
pos[:, [0, 1]] = pos[:, [1, 0]] * [-1, 1]
return make_dig_montage(
ch_pos=dict(zip(ch_names, pos)),
coord_frame='head',
)