def test_model_H_conversion(L=6):
bc = 'finite'
model_params = {'L': L, 'hz': np.random.random([L]), 'bc_MPS': bc}
m = XXZChain(model_params)
# can we run the conversion?
# conversion from bond to MPO in NearestNeighborModel
H_MPO = m.calc_H_MPO_from_bond()
# conversion from MPO to bond in MPOModel
H_bond = m.calc_H_bond_from_MPO()
# compare: did we get the correct result?
ED = ExactDiag(m)
ED.build_full_H_from_bonds()
H0 = ED.full_H # this should be correct
ED.full_H = None
m.H_MPO = H_MPO
ED.build_full_H_from_mpo()
full_H_mpo = ED.full_H # the one generated by NearstNeighborModel.calc_H_MPO_from_bond()
print("npc.norm(H0 - full_H_mpo) = ", npc.norm(H0 - full_H_mpo))
assert npc.norm(H0 -
full_H_mpo) < 1.e-14 # round off errors on order of 1.e-15
m.H_bond = H_bond
ED.full_H = None
ED.build_full_H_from_bonds()
full_H_bond = ED.full_H # the one generated by NearstNeighborModel.calc_H_MPO_from_bond()
print("npc.norm(H0 - full_H_bond) = ", npc.norm(H0 - full_H_bond))
assert npc.norm(
H0 - full_H_bond) < 1.e-14 # round off errors on order of 1.e-15
def test_CouplingMPOModel_group():
m1 = MyMod(dict(x=0.5, L=5, bc_MPS='finite'))
model_params = {'L': 6, 'hz': np.random.random([6]), 'bc_MPS': 'finite'}
m2 = XXZChain(model_params)
for m in [m1, m2]:
print("model = ", m)
assert m.H_MPO.max_range == 1
# test grouping sites
ED = ExactDiag(m)
# ED.build_full_H_from_mpo()
ED.build_full_H_from_bonds()
m.group_sites(n=2)
assert m.H_MPO.max_range == 1
ED_gr = ExactDiag(m)
ED_gr.build_full_H_from_mpo()
H = ED.full_H.split_legs().to_ndarray()
Hgr = ED_gr.full_H.split_legs()
Hgr.idrop_labels()
Hgr = Hgr.split_legs().to_ndarray()
assert np.linalg.norm(H - Hgr) < 1.e-14
ED_gr.full_H = None
ED_gr.build_full_H_from_bonds()
Hgr = ED_gr.full_H.split_legs()
Hgr.idrop_labels()
Hgr = Hgr.split_legs().to_ndarray()
assert np.linalg.norm(H - Hgr) < 1.e-14
def test_CouplingMPOModel_group():
m = MyMod(dict(x=0.5, L=5, bc_MPS='finite'))
assert m.H_MPO.max_range == 1
# test grouping sites
ED = ExactDiag(m)
# ED.build_full_H_from_mpo()
ED.build_full_H_from_bonds()
m.group_sites(n=2)
assert m.H_MPO.max_range == 1
ED_gr = ExactDiag(m)
ED_gr.build_full_H_from_mpo()
H = ED.full_H.split_legs().to_ndarray()
Hgr = ED_gr.full_H.split_legs()
Hgr.idrop_labels()
Hgr = Hgr.split_legs().to_ndarray()
assert np.linalg.norm(H - Hgr) == 0
ED_gr.full_H = None
ED_gr.build_full_H_from_bonds()
Hgr = ED_gr.full_H.split_legs()
Hgr.idrop_labels()
Hgr = Hgr.split_legs().to_ndarray()
assert np.linalg.norm(H - Hgr) == 0
def test_CouplingMPOModel_group():
class MyMod(model.CouplingMPOModel, model.NearestNeighborModel):
def __init__(self, model_params):
model.CouplingMPOModel.__init__(self, model_params)
def init_sites(self, model_params):
return tenpy.networks.site.SpinHalfSite('parity')
def init_terms(self, model_params):
x = get_parameter(model_params, 'x', 1., self.name)
self.add_onsite_term(0.25, 0, 'Sz')
self.add_onsite_term(0.25, 4, 'Sz')
self.add_coupling_term(x, 0, 1, 'Sx', 'Sx')
self.add_coupling_term(2. * x, 1, 2, 'Sy', 'Sy')
self.add_coupling_term(3. * x, 3, 4, 'Sy', 'Sy')
m = MyMod(dict(x=0.5, L=5, bc_MPS='finite'))
m.test_sanity()
for Hb in m.H_bond:
if Hb is not None:
Hb.test_sanity()
# test grouping sites
ED = ExactDiag(m)
# ED.build_full_H_from_mpo()
ED.build_full_H_from_bonds()
m.group_sites(n=2)
ED_gr = ExactDiag(m)
ED_gr.build_full_H_from_mpo()
H = ED.full_H.split_legs().to_ndarray()
Hgr = ED_gr.full_H.split_legs()
Hgr.idrop_labels()
Hgr = Hgr.split_legs().to_ndarray()
assert np.linalg.norm(H - Hgr) == 0
ED_gr.full_H = None
ED_gr.build_full_H_from_bonds()
Hgr = ED_gr.full_H.split_legs()
Hgr.idrop_labels()
Hgr = Hgr.split_legs().to_ndarray()
assert np.linalg.norm(H - Hgr) == 0