def test_center():
"""Test getting and setting the center."""
ellipsoid = Ellipsoid(1, 2, 3)
assert all(ellipsoid.center == (0, 0, 0))
center = (1, 1, 1)
ellipsoid.center = center
assert all(ellipsoid.center == center)
def test_inertia_tensor(a, b, c, center):
# First just test a sphere.
ellipsoid = Ellipsoid(a, a, a)
assert np.all(ellipsoid.inertia_tensor >= 0)
volume = ellipsoid.volume
expected = [2 / 5 * volume * a**2] * 3
np.testing.assert_allclose(np.diag(ellipsoid.inertia_tensor), expected)
ellipsoid.center = center
expected = translate_inertia_tensor(center, np.diag(expected), volume)
np.testing.assert_allclose(ellipsoid.inertia_tensor, expected)