def test_hubbard_square_lattice_2x2():
for periodic in (True, False):
lattice = HubbardSquareLattice(2, 2, periodic=periodic)
assert lattice.n_sites == 4
assert len(tuple(lattice.neighbors_iter(False))) == 4
assert len(tuple(lattice.neighbors_iter())) == 8
assert len(tuple(lattice.diagonal_neighbors_iter(False))) == 2
assert len(tuple(lattice.diagonal_neighbors_iter())) == 4
def test_hubbard_square_lattice_1xd(d):
for shape, periodic in itertools.product(((1, d), (d, 1)), (True, False)):
lattice = HubbardSquareLattice(*shape, periodic=periodic)
assert lattice.n_sites == d
assert (len(tuple(lattice.neighbors_iter())) ==
2 * len(tuple(lattice.neighbors_iter(False))) == 2 *
(d - (not periodic)))
assert (len(tuple(lattice.diagonal_neighbors_iter())) == len(
tuple(lattice.diagonal_neighbors_iter(False))) == 0)
def test_hubbard_square_lattice_2xd(d):
for shape, periodic in itertools.product(((2, d), (d, 2)), (True, False)):
lattice = HubbardSquareLattice(*shape, periodic=periodic)
assert lattice.n_sites == 2 * d
n_neighbor_pairs = 2 * (2 * (d - (not periodic)) + d)
assert (len(tuple(lattice.neighbors_iter())) == 2 *
len(tuple(lattice.neighbors_iter(False))) == n_neighbor_pairs)
n_diagonal_neighbor_pairs = 4 * (d - (not periodic))
assert (len(tuple(lattice.diagonal_neighbors_iter())) ==
2 * len(tuple(lattice.diagonal_neighbors_iter(False))) ==
n_diagonal_neighbor_pairs)
def test_hubbard_square_lattice_neighbors(x, y):
for periodic in (True, False):
lattice = HubbardSquareLattice(x, y, periodic=periodic)
n_horizontal_neighbors = 2 * y * (x - (not periodic))
assert (len(tuple(lattice.horizontal_neighbors_iter())) ==
n_horizontal_neighbors)
n_vertical_neighbors = 2 * x * (y - (not periodic))
assert (len(tuple(lattice.vertical_neighbors_iter())) ==
n_vertical_neighbors)
n_diagonal_neighbors = 4 * (x - (not periodic)) * (y - (not periodic))
assert (len(tuple(lattice.diagonal_neighbors_iter())) ==
n_diagonal_neighbors)