def test_hypercubic_lattice():
lattice = HypercubicLattice([8, 8])
assert eval(repr(lattice)) == lattice
point = LatticeSite([0, 0])
expected = set([
LatticeSite([0, 1]),
LatticeSite([1, 0]),
LatticeSite([0, -1]),
LatticeSite([-1, 0]),
])
assert set(lattice.nearest_neighbors(point)) == expected
assert len(lattice.nearest_neighbors(point)) == 2 * len(lattice.nearest_neighbors(point, False))
def test_nearest_neighbors_distance(self):
lattice = HypercubicLattice([8, 16, 24])
nn = lattice.nearest_neighbors(LatticeSite([0, 0, 0]))
nn = [lattice.spatial_coordinates(point) for point in nn]
norms = [sum(a * a for a in point) for point in nn]
assert min(norms) + .0000001 > max(norms)
