def test_number_nn():
s = site.SpinHalfSite('Sz')
chain = lattice.Chain(2, s)
assert chain.number_nearest_neighbors() == 2
assert chain.number_next_nearest_neighbors() == 2
ladd = lattice.Ladder(2, s)
assert ladd.number_nearest_neighbors(0) == 3
assert ladd.number_nearest_neighbors(1) == 3
assert ladd.number_next_nearest_neighbors(0) == 2
assert ladd.number_next_nearest_neighbors(1) == 2
square = lattice.Square(2, 2, s)
assert square.number_nearest_neighbors() == 4
assert square.number_next_nearest_neighbors() == 4
triang = lattice.Triangular(2, 2, s)
assert triang.number_nearest_neighbors() == 6
assert triang.number_next_nearest_neighbors() == 6
hc = lattice.Honeycomb(2, 2, s)
assert hc.number_nearest_neighbors(0) == 3
assert hc.number_nearest_neighbors(1) == 3
assert hc.number_next_nearest_neighbors(0) == 6
assert hc.number_next_nearest_neighbors(1) == 6
kag = lattice.Kagome(2, 2, s)
assert kag.number_nearest_neighbors(0) == 4
assert kag.number_nearest_neighbors(1) == 4
assert kag.number_nearest_neighbors(2) == 4
assert kag.number_next_nearest_neighbors(0) == 4
assert kag.number_next_nearest_neighbors(1) == 4
assert kag.number_next_nearest_neighbors(2) == 4
def test_pairs():
lattices = [
lattice.Chain(2, None),
lattice.Ladder(2, None),
lattice.Square(2, 2, None),
lattice.Triangular(2, 2, None),
lattice.Honeycomb(2, 2, None),
lattice.Kagome(2, 2, None)
]
for lat in lattices:
print(lat.__class__.__name__)
found_dist_pairs = lat.find_coupling_pairs(5, 3.)
dists = sorted(found_dist_pairs.keys())
for i, name in enumerate([
'nearest_neighbors', 'next_nearest_neighbors', 'next_next_nearest_neighbors',
'fourth_nearest_neighbors', 'fifth_nearest_neighbors'
]):
if name not in lat.pairs:
assert i > 2 # all of them should define up to next_next_nearest_neighbors
continue
print(name)
defined_pairs = lat.pairs[name]
found_pairs = found_dist_pairs[dists[i]]
assert len(defined_pairs) == len(found_pairs)
defined_pairs = pairs_with_reversed(defined_pairs)
found_pairs = pairs_with_reversed(found_pairs)
assert defined_pairs == found_pairs
def test_lattice_order():
s = site.SpinHalfSite('Sz')
# yapf: disable
chain = lattice.Chain(4, s)
order_default = np.array([[0, 0], [1, 0], [2, 0], [3, 0]])
npt.assert_equal(chain.order, order_default)
chain = lattice.Chain(4, s, order='folded')
order_folded = np.array([[0, 0], [3, 0], [1, 0], [2, 0]])
npt.assert_equal(chain.order, order_folded)
chain = lattice.Chain(5, s, order='folded')
order_folded = np.array([[0, 0], [4, 0], [1, 0], [3, 0], [2, 0]])
ladder = lattice.Ladder(3, s, order='folded')
order_folded = np.array([[0, 0], [0, 1], [2, 0], [2, 1], [1, 0], [1, 1]])
npt.assert_equal(ladder.order, order_folded)
square = lattice.Square(2, 2, s, order='default')
order_default = np.array([[0, 0, 0], [0, 1, 0], [1, 0, 0], [1, 1, 0]])
npt.assert_equal(square.order, order_default)
square = lattice.Square(4, 3, s, order='snake')
order_snake = np.array([[0, 0, 0], [0, 1, 0], [0, 2, 0], [1, 2, 0], [1, 1, 0], [1, 0, 0],
[2, 0, 0], [2, 1, 0], [2, 2, 0], [3, 2, 0], [3, 1, 0], [3, 0, 0]])
npt.assert_equal(square.order, order_snake)
square = lattice.Square(2, 3, s, order=("standard", (True, False), (1, 0)))
order_Fsnake = np.array([[0, 0, 0], [1, 0, 0], [1, 1, 0], [0, 1, 0], [0, 2, 0], [1, 2, 0]])
npt.assert_equal(square.order, order_Fsnake)
hc = lattice.Honeycomb(2, 3, s, order='default')
order_hc_def = np.array([[0, 0, 0], [0, 1, 0], [0, 2, 0], [0, 0, 1], [0, 1, 1], [0, 2, 1],
[1, 0, 0], [1, 1, 0], [1, 2, 0], [1, 0, 1], [1, 1, 1], [1, 2, 1]])
npt.assert_equal(hc.order, order_hc_def)
hc = lattice.Honeycomb(2, 3, s, order=('standard', (True, False, False), (0.3, 0.1, -1.)))
order_hc_mix = np.array([[0, 0, 0], [1, 0, 0], [1, 1, 0], [0, 1, 0], [0, 2, 0], [1, 2, 0],
[0, 0, 1], [1, 0, 1], [1, 1, 1], [0, 1, 1], [0, 2, 1], [1, 2, 1]])
npt.assert_equal(hc.order, order_hc_mix)
kag = lattice.Kagome(2, 3, s, order=('grouped', [[1], [0, 2]]))
order_kag_gr = np.array([[0, 0, 1], [0, 1, 1], [0, 2, 1], [0, 0, 0], [0, 0, 2], [0, 1, 0],
[0, 1, 2], [0, 2, 0], [0, 2, 2],
[1, 0, 1], [1, 1, 1], [1, 2, 1], [1, 0, 0], [1, 0, 2], [1, 1, 0],
[1, 1, 2], [1, 2, 0], [1, 2, 2]])
npt.assert_equal(kag.order, order_kag_gr)
kag = lattice.Kagome(2, 4, s, order=('grouped', [[0], [2, 1]], [1, 0, 2]))
order_kag_gr = np.array([[0, 0, 0], [1, 0, 0], [0, 0, 2], [0, 0, 1], [1, 0, 2], [1, 0, 1],
[0, 1, 0], [1, 1, 0], [0, 1, 2], [0, 1, 1], [1, 1, 2], [1, 1, 1],
[0, 2, 0], [1, 2, 0], [0, 2, 2], [0, 2, 1], [1, 2, 2], [1, 2, 1],
[0, 3, 0], [1, 3, 0], [0, 3, 2], [0, 3, 1], [1, 3, 2], [1, 3, 1]])
npt.assert_equal(kag.order, order_kag_gr)
def test_CouplingModel_fermions():
for bc, bc_MPS in zip(['open', 'periodic'], ['finite', 'infinite']):
fermion_lat = lattice.Chain(5, fermion_site, bc=bc, bc_MPS=bc_MPS)
M = model.CouplingModel(fermion_lat)
M.add_coupling(1.2, 0, 'Cd', 0, 'C', 1, 'JW')
M.add_coupling(1.2, 0, 'Cd', 0, 'C', -1, 'JW')
M.test_sanity()
M.calc_H_MPO()
M.calc_H_bond()
def test_CouplingModel():
for bc in ['open', 'periodic']:
spin_half_lat = lattice.Chain(5, spin_half_site, bc=bc, bc_MPS='finite')
M = model.CouplingModel(spin_half_lat)
M.add_coupling(1.2, 0, 'Sz', 0, 'Sz', 1)
M.test_sanity()
M.calc_H_MPO()
if bc == 'periodic':
with pytest.raises(ValueError, match="nearest neighbor"):
M.calc_H_bond() # should raise a ValueError
# periodic bc but finite bc_MPS leads to a long-range coupling
else:
M.calc_H_bond()
def test_CouplingModel():
spin_half_lat = lattice.Chain(5, spin_half_site, bc_MPS='finite')
for bc in ['open', 'periodic']:
M = model.CouplingModel(spin_half_lat, bc)
M.add_coupling(1.2, 0, 'Sz', 0, 'Sz', 1)
M.test_sanity()
M.calc_H_MPO()
if bc == 'periodic':
with nose.tools.assert_raises(ValueError):
M.calc_H_bond() # should raise a ValueError
# periodic bc but finite bc_MPS leads to a long-range coupling
else:
M.calc_H_bond()
def test_number_nn():
s = site.SpinHalfSite('Sz')
chain = lattice.Chain(2, s)
assert chain.number_nearest_neighbors() == 2
assert chain.number_next_nearest_neighbors() == 2
square = lattice.Square(2, 2, s)
print(square.number_next_nearest_neighbors())
assert square.number_nearest_neighbors() == 4
assert square.number_next_nearest_neighbors() == 4
hc = lattice.Honeycomb(2, 2, s, s)
assert hc.number_nearest_neighbors(0) == 3
assert hc.number_nearest_neighbors(1) == 3
assert hc.number_next_nearest_neighbors(0) == 6
assert hc.number_next_nearest_neighbors(1) == 6
def test_number_nn():
s = site.SpinHalfSite('Sz')
chain = lattice.Chain(2, s)
assert chain.count_neighbors() == 2
assert chain.count_neighbors(key='next_nearest_neighbors') == 2
ladd = lattice.Ladder(2, s)
for u in [0, 1]:
assert ladd.count_neighbors(u) == 3
assert ladd.count_neighbors(u, key='next_nearest_neighbors') == 2
square = lattice.Square(2, 2, s)
assert square.count_neighbors() == 4
assert square.count_neighbors(key='next_nearest_neighbors') == 4
triang = lattice.Triangular(2, 2, s)
assert triang.count_neighbors() == 6
assert triang.count_neighbors(key='next_nearest_neighbors') == 6
hc = lattice.Honeycomb(2, 2, s)
for u in [0, 1]:
assert hc.count_neighbors(u) == 3
assert hc.count_neighbors(u, key='next_nearest_neighbors') == 6
kag = lattice.Kagome(2, 2, s)
for u in [0, 1, 2]:
assert kag.count_neighbors(u) == 4
assert kag.count_neighbors(u, key='next_nearest_neighbors') == 4
"""A collection of tests for (classes in) :mod:`tenpy.models.model`.
.. todo ::
A lot more to test, e.g. conversions of the different models
"""
# Copyright 2018 TeNPy Developers
import itertools
from tenpy.models import model, lattice
import tenpy.networks.site
import tenpy.linalg.np_conserved as npc
import test_mpo
spin_half_site = tenpy.networks.site.SpinHalfSite('Sz')
spin_half_lat = lattice.Chain(2, spin_half_site)
fermion_site = tenpy.networks.site.FermionSite('N')
fermion_lat = lattice.Chain(5, fermion_site)
def test_CouplingModel():
for bc in ['open', 'periodic']:
M = model.CouplingModel(spin_half_lat, bc)
M.add_coupling(1.2, 0, 'Sz', 0, 'Sz', 1)
M.test_sanity()
M = model.CouplingModel(fermion_lat, bc)
M.add_coupling(1.2, 0, 'Cd', 0, 'C', 1, 'JW')
M.test_sanity()
