def test_error_bound_superset_hubbard(self):
FO = FermionOperator
terms = []
for i in [0, 2]:
terms.append(
FO(((i, 1), (i + 1, 0)), -0.01) + FO(((i + 1, 1),
(i, 0)), -0.01))
for i in [0, 1]:
terms.append(
FO(((i, 1), (i + 2, 0)), -0.03) + FO(((i + 2, 1),
(i, 0)), -0.03))
terms.append(FO(((i + 2, 1), (i, 1), (i + 2, 0), (i, 0)), 3.))
indices = [
set([0, 1]),
set([2, 3]),
set([0, 2]),
set([0, 2]),
set([1, 3]),
set([1, 3])
]
is_hopping_operator = [True, True, True, False, True, False]
self.assertAlmostEqual(
low_depth_second_order_trotter_error_bound(terms, indices,
is_hopping_operator),
0.0608)
def test_error_bound_using_info_even_side_length(self):
# Generate the Hamiltonian.
hamiltonian = normal_ordered(
fermi_hubbard(4, 4, 0.5, 0.2, periodic=False))
hamiltonian.compress()
# Unpack result into terms, indices they act on, and whether they're
# hopping operators.
result = simulation_ordered_grouped_hubbard_terms_with_info(
hamiltonian)
terms, indices, is_hopping = result
self.assertAlmostEqual(
low_depth_second_order_trotter_error_bound(terms, indices,
is_hopping), 13.59)
def test_error_bound_using_info_1d(self):
# Generate the Hamiltonian.
grid = hypercube_grid_with_given_wigner_seitz_radius_and_filling(
dimension=1, grid_length=4, wigner_seitz_radius=10.)
hamiltonian = normal_ordered(
jellium_model(grid, spinless=True, plane_wave=False))
hamiltonian.compress()
# Unpack result into terms, indices they act on, and whether they're
# hopping operators.
result = simulation_ordered_grouped_low_depth_terms_with_info(
hamiltonian)
terms, indices, is_hopping = result
self.assertAlmostEqual(
low_depth_second_order_trotter_error_bound(terms, indices,
is_hopping),
7.4239378440953283)
def test_error_bound(self):
self.assertAlmostEqual(
low_depth_second_order_trotter_error_bound(self.terms,
jellium_only=True),
6.92941899358)