def test_nonlocal_sum():
H = LocalSpace(hs_name(), dimension=5)
a = Create(hs=H).adjoint()
H2 = LocalSpace(hs_name(), basis=("e", "g", "h"))
sigma = LocalSigma('g', 'e', hs=H2)
assert convert_to_qutip(a + sigma)**2 == convert_to_qutip(
(a + sigma) * (a + sigma))
def disjunct_commutative_test_data():
A1 = OperatorSymbol("A", hs=1)
B1 = OperatorSymbol("B", hs=1)
C1 = OperatorSymbol("C", hs=1)
A2 = OperatorSymbol("A", hs=2)
B2 = OperatorSymbol("B", hs=2)
A3 = OperatorSymbol("A", hs=3)
B4 = OperatorSymbol("B", hs=4)
tr_A1 = tr(A1, over_space=1)
tr_A2 = tr(A2, over_space=2)
A1_m = OperatorSymbol("A", hs=LocalSpace(1, order_index=2))
B1_m = OperatorSymbol("B", hs=LocalSpace(1, order_index=2))
B2_m = OperatorSymbol("B", hs=LocalSpace(2, order_index=1))
ket_0 = BasisKet(0, hs=1)
ket_1 = BasisKet(1, hs=1)
ketbra = KetBra(ket_0, ket_1)
braket = BraKet(ket_1, ket_1)
# fmt: off
return [
([B2, B1, A1], [B1, A1, B2]),
([B2_m, B1_m, A1_m], [B2_m, B1_m, A1_m]),
([B1_m, A1_m, B2_m], [B2_m, B1_m, A1_m]),
([B1, A2, C1, tr_A2], [tr_A2, B1, C1, A2]),
([A1, B1 + B2], [A1, B1 + B2]),
([B1 + B2, A1], [B1 + B2, A1]),
([A3 + B4, A1 + A2], [A1 + A2, A3 + B4]),
([A1 + A2, A3 + B4], [A1 + A2, A3 + B4]),
([B4 + A3, A2 + A1], [A1 + A2, A3 + B4]),
([tr_A2, tr_A1], [tr_A1, tr_A2]),
([A2, ketbra, A1], [ketbra, A1, A2]),
([A2, braket, A1], [braket, A1, A2]),
]
def test_substitute_sub_expr(H_JC):
"""Test that we can replace non-atomic sub-expressions"""
hil_a = LocalSpace('A')
hil_b = LocalSpace('B')
omega_a, omega_b, g = symbols('omega_a, omega_b, g')
a = Destroy(hs=hil_a)
a_dag = a.dag()
b = Destroy(hs=hil_b)
b_dag = b.dag()
n_op_a = OperatorSymbol('n', hs=hil_a)
n_op_b = OperatorSymbol('n', hs=hil_b)
x_op = OperatorSymbol('x', hs=H_JC.space)
mapping = {
a_dag * a: n_op_a,
b_dag * b: n_op_b,
(a_dag * b + b_dag * a): x_op + x_op.dag(),
}
H2_expected = (omega_a * n_op_a + omega_b * n_op_b + 2 * g *
(x_op + x_op.dag()))
H2 = H_JC.substitute(mapping)
assert H2 == H2_expected
H2 = substitute(H_JC, mapping)
assert H2 == H2_expected
def testHilbertSpace(self):
h1 = LocalSpace("h1")
h2 = LocalSpace("h2")
a = SuperOperatorSymbol("a", hs=h1)
b = SuperOperatorSymbol("b", hs=h2)
assert a.space == h1
assert (a * b).space == h1 * h2
def test_symbol():
expN = OperatorSymbol("expN", hs=1)
hs1 = LocalSpace("sym1", dimension=10)
hs2 = LocalSpace("sym2", dimension=5)
N = Create(hs=hs1) * Destroy(hs=hs1)
M = Create(hs=hs2) * Destroy(hs=hs2)
converter1 = {expN: convert_to_qutip(N).expm()}
expNq = convert_to_qutip(expN, mapping=converter1)
assert (np.linalg.norm(expNq.data.toarray() -
(convert_to_qutip(N).expm().data.toarray())) < 1e-8)
expNMq = convert_to_qutip(expN * M, mapping=converter1)
assert (np.linalg.norm(expNMq.data.toarray() - (qutip.tensor(
convert_to_qutip(N).expm(), convert_to_qutip(M)).data.toarray())) <
1e-8)
converter2 = {expN: lambda expr: convert_to_qutip(N).expm()}
expNq = convert_to_qutip(expN, mapping=converter2)
assert (np.linalg.norm(expNq.data.toarray() -
(convert_to_qutip(N).expm().data.toarray())) < 1e-8)
expNMq = convert_to_qutip(expN * M, mapping=converter1)
assert (np.linalg.norm(expNMq.data.toarray() - (qutip.tensor(
convert_to_qutip(N).expm(), convert_to_qutip(M)).data.toarray())) <
1e-8)
def test_tensor_product():
H = LocalSpace(hs_name(), dimension=5)
a = Create(hs=H).adjoint()
H2 = LocalSpace(hs_name(), basis=("e", "g", "h"))
sigma = LocalSigma('g', 'e', hs=H2)
assert convert_to_qutip(sigma * a) == qutip.tensor(convert_to_qutip(a),
convert_to_qutip(sigma))
def test_finditer():
h1 = LocalSpace("h1")
a = OperatorSymbol("a", hs=h1)
b = OperatorSymbol("b", hs=h1)
c = OperatorSymbol("c", hs=h1)
h1_custom = LocalSpace("h1", local_identifiers={'Create': 'c'})
c_local = Create(hs=h1_custom)
expr = 2 * (a * b * c - b * c * a + a * b)
pat = wc('sym', head=OperatorSymbol)
for m in pat.finditer(expr):
assert 'sym' in m
matches = list(pat.finditer(expr))
assert len(matches) == 8
op_symbols = [m['sym'] for m in matches]
assert set(op_symbols) == {a, b, c}
op = wc(head=Operator)
three_factors = pattern(OperatorTimes, op, op, op).findall(expr)
assert three_factors == [a * b * c, b * c * a]
assert len(list(pattern(LocalOperator).finditer(expr))) == 0
assert (
len(
list(
pattern(LocalOperator).finditer(expr.substitute({c: c_local}))
)
)
== 2
)
def test_substitute_str(H_JC):
"""Test that we can substitute e.g. label strings"""
H2 = H_JC.substitute({'A': '1', 'B': '2'})
hs_mapping = {
LocalSpace('A'): LocalSpace('1'),
LocalSpace('B'): LocalSpace('2'),
}
assert H2 == H_JC.substitute(hs_mapping)
def test_instantiate_with_basis():
"""Test that a local space can be instantiated with an explicit basis"""
hs1 = LocalSpace('1', basis=(0, 1))
assert hs1.dimension == 2
assert hs1.basis_labels == ('0', '1')
hs1 = LocalSpace('1', basis=['g', 'e'])
assert hs1.dimension == 2
assert hs1.basis_labels == ('g', 'e')
def testAdditionToSuperOperator(self):
h1 = LocalSpace("h1")
h2 = LocalSpace("h2")
a = SuperOperatorSymbol("a", hs=h1)
b = SuperOperatorSymbol("b", hs=h2)
assert a + b == b + a
assert a + b == SuperOperatorPlus(a, b)
assert (a + b).space == h1 * h2
def test_commutator_hs():
"""Test that commutator is in the correct Hilbert space"""
hs1 = LocalSpace("1")
hs2 = LocalSpace("2")
A = OperatorSymbol('A', hs=hs1)
B = OperatorSymbol('B', hs=hs2)
C = OperatorSymbol('C', hs=hs2)
assert Commutator.create(B, C).space == hs2
assert Commutator.create(B, A + C).space == hs1 * hs2
def test_custom_localspace_identifier_hash():
"""Test hashes for expressions with different local_identifiers for their
Hilbert spaces have different hashes"""
hs1 = LocalSpace(1)
hs1_custom = LocalSpace(1, local_identifiers={'Destroy': 'b'})
assert hash(hs1) != hash(hs1_custom)
a = Destroy(hs=hs1)
b = Destroy(hs=hs1_custom)
assert hash(a) != hash(b)
def test_product_space_order():
H1 = LocalSpace(1)
H2 = LocalSpace('2')
assert H1 * H2 == H2 * H1
assert (H1 * H2).operands == (H1, H2)
H1 = LocalSpace(1)
H2 = LocalSpace('2', order_index=2)
H3 = LocalSpace(3, order_index=1)
assert (H1 * H2 * H3).operands == (H3, H2, H1)
def test_dimension():
h1 = LocalSpace("h1", dimension=10)
h2 = LocalSpace("h2", dimension=20)
h3 = LocalSpace("h3")
h4 = LocalSpace("h4", dimension=100)
assert (h1 * h2).dimension == h1.dimension * h2.dimension
with pytest.raises(BasisNotSetError):
h3.dimension
assert h4.dimension == 100
def test_hilbertspace_free_symbols():
"""Test that Hilbert spaces with an indexed name return the index symbol in
free_symbols"""
i, j = symbols('i, j', cls=IdxSym)
assert LocalSpace(1).free_symbols == set()
hs_i = LocalSpace(StrLabel(i))
hs_j = LocalSpace(StrLabel(j))
assert hs_i.free_symbols == {i}
assert hs_j.free_symbols == {j}
assert (hs_i * hs_j).free_symbols == {i, j}
def testZeroOne(self):
h1 = LocalSpace("h1")
h2 = LocalSpace("h2")
a = OperatorSymbol("a", hs=h1)
B = SuperOperatorSymbol("B", hs=h2)
z = ZeroSuperOperator
one = IdentitySuperOperator
assert one * a == a
assert z * a == ZeroOperator
def test_op_product_space():
"""Test that a product of operators has the correct Hilbert space"""
a = Destroy(hs=1)
b = Destroy(hs=2)
p = a * b
assert p.space == ProductSpace(LocalSpace(1), LocalSpace(2))
assert not p.space.has_basis
hs1 = LocalSpace(1, dimension=3)
a = a.substitute({LocalSpace(1): hs1})
p = a * b
assert p.space == ProductSpace(hs1, LocalSpace(2))
assert not p.space.has_basis
hs2 = LocalSpace(2, dimension=2)
b = b.substitute({LocalSpace(2): hs2})
p = a * b
ps = ProductSpace(hs1, hs2)
assert p.space == ps
assert p.space.dimension == 6
assert p.space.basis_labels == ('0,0', '0,1', '1,0', '1,1', '2,0', '2,1')
hs1_2 = LocalSpace(1, basis=('g', 'e'))
hs2_2 = LocalSpace(2, basis=('g', 'e'))
p = p.substitute({hs1: hs1_2, hs2: hs2_2})
assert p.space.dimension == 4
assert p.space.basis_labels == ('g,g', 'g,e', 'e,g', 'e,e')
b = b.substitute({hs2: hs1})
p = a * b
assert p.space == hs1
assert p.space.dimension == 3
assert p.space.basis_labels == ('0', '1', '2')
def test_disjunct_hs():
"""Test that commutator of objects in disjunt Hilbert spaces is zero"""
hs1 = LocalSpace("1")
hs2 = LocalSpace("2")
alpha, beta = symbols('alpha, beta')
A = OperatorSymbol('A', hs=hs1)
B = OperatorSymbol('B', hs=hs2)
assert Commutator.create(A, B) == ZeroOperator
assert Commutator.create(alpha, beta) == ZeroOperator
assert Commutator.create(alpha, B) == ZeroOperator
assert Commutator.create(A, beta) == ZeroOperator
def H_JC():
hil_a = LocalSpace('A')
hil_b = LocalSpace('B')
a = Destroy(hs=hil_a)
a_dag = a.dag()
b = Destroy(hs=hil_b)
b_dag = b.dag()
omega_a, omega_b, g = symbols('omega_a, omega_b, g')
H = (omega_a * a_dag * a + omega_b * b_dag * b + 2 * g *
(a_dag * b + b_dag * a))
return H
def test_basis_change():
"""Test that we can change the basis of an Expression's Hilbert space
through substitution"""
a = Destroy(hs=1)
assert a.space == LocalSpace('1')
assert not a.space.has_basis
subs = {LocalSpace('1'): LocalSpace('1', basis=(-1, 0, 1))}
b = a.substitute(subs)
assert str(a) == str(b)
assert a != b
assert b.space.dimension == 3
assert b.space.basis_labels == ('-1', '0', '1')
def testSPreSPostRules(self):
h1 = LocalSpace("h1")
h2 = LocalSpace("h2")
d = OperatorSymbol("d", hs=h1)
e = OperatorSymbol("e", hs=h1)
dpre = SPre(d)
epre = SPre(e)
dpost = SPost(d)
epost = SPost(e)
assert dpre * epre == SPre(d * e)
assert dpost * epost == SPost(e * d)
assert dpost * epre == SPre(e) * SPost(d)
def test_space_ordering():
h1 = LocalSpace("h1")
h2 = LocalSpace("h2")
h3 = LocalSpace("h3")
assert h1 <= h1
assert h1 <= (h1 * h2)
assert not (h1 <= h2)
assert not (h1 < h1)
assert TrivialSpace < h1 < FullSpace
assert h1 >= h1
assert h1 * h2 > h2
assert not (h1 * h2 > h3)
def testOrdering(self):
h1 = LocalSpace("h1")
h2 = LocalSpace("h2")
a = SuperOperatorSymbol("a", hs=h1)
b = SuperOperatorSymbol("b", hs=h2)
c = SuperOperatorSymbol("c", hs=h2)
dpre = SPre(SuperOperatorSymbol("d", hs=h1))
epre = SPre(SuperOperatorSymbol("e", hs=h1))
dpost = SPost(SuperOperatorSymbol("d", hs=h1))
epost = SPost(SuperOperatorSymbol("e", hs=h1))
assert a * b == SuperOperatorTimes(a, b)
assert b * a == a * b
assert c * a * b * c * a == SuperOperatorTimes(a, a, c, b, c)
def test_operations():
h1 = LocalSpace("h1")
h2 = LocalSpace("h2")
h3 = LocalSpace("h3")
h123 = h1 * h2 * h3
h12 = h1 * h2
h23 = h2 * h3
h13 = h1 * h3
assert h12 * h13 == h123
assert h12 / h13 == h2
assert h12 & h13 == h1
assert (h12 / h13) * (h13 & h12) == h12
assert h1 & h12 == h1
def test_exception_teardown():
"""Test that teardown works when breaking out due to an exception"""
class TemporaryRulesException(Exception):
pass
h1 = LocalSpace("h1")
a = OperatorSymbol("a", hs=h1)
b = OperatorSymbol("b", hs=h1)
hs_repr = "LocalSpace('h1')"
rule_name = 'extra'
rule = (pattern_head(6, a), lambda: b)
simplifications = OperatorPlus.simplifications
try:
with temporary_rules(ScalarTimesOperator, OperatorPlus):
ScalarTimesOperator.add_rule(rule_name, rule[0], rule[1])
OperatorPlus.simplifications.remove(scalars_to_op)
raise TemporaryRulesException
except TemporaryRulesException:
assert rule not in ScalarTimesOperator._rules.values()
assert scalars_to_op in OperatorPlus.simplifications
finally:
# Even if this failed we don't want to make a mess for other tests
try:
ScalarTimesOperator.del_rules(rule_name)
except KeyError:
pass
OperatorPlus.simplifications = simplifications
def testSubtraction(self):
hs = LocalSpace("hs")
a = SuperOperatorSymbol("a", hs=hs)
b = SuperOperatorSymbol("b", hs=hs)
z = ZeroSuperOperator
assert a - a == z
assert a - b == SuperOperatorPlus(a, ScalarTimesSuperOperator(-1, b))
def testCommutativity(self):
h1 = LocalSpace("h1")
assert SuperOperatorSymbol("A", hs=h1) + SuperOperatorSymbol(
"B", hs=h1
) == (
SuperOperatorSymbol("B", hs=h1) + SuperOperatorSymbol("A", hs=h1)
)
def test_commutator_expand_evaluate():
"""Test expansion and evaluation of commutators"""
hs = LocalSpace("0")
A = OperatorSymbol('A', hs=hs)
B = OperatorSymbol('B', hs=hs)
C = OperatorSymbol('C', hs=hs)
D = OperatorSymbol('D', hs=hs)
E = OperatorSymbol('E', hs=hs)
expr = Commutator(A, B * C * D * E)
res = (B * C * D * Commutator(A, E) + B * C * Commutator(A, D) * E +
B * Commutator(A, C) * D * E + Commutator(A, B) * C * D * E)
assert expand_commutators_leibniz(expr) == res
assert expr.doit([Commutator]) == (A * B * C * D * E - B * C * D * E * A)
assert res.doit([Commutator
]).expand() == (A * B * C * D * E - B * C * D * E * A)
assert expand_commutators_leibniz(expr, expand_expr=False) == (
B * (C * (D * Commutator(A, E) + Commutator(A, D) * E) +
Commutator(A, C) * D * E) + Commutator(A, B) * C * D * E)
expr = Commutator(A * B * C, D)
assert expand_commutators_leibniz(expr) == (A * B * Commutator(C, D) +
A * Commutator(B, D) * C +
Commutator(A, D) * B * C)
expr = Commutator(A * B, C * D)
assert expand_commutators_leibniz(expr) == (A * Commutator(B, C) * D +
C * A * Commutator(B, D) +
C * Commutator(A, D) * B +
Commutator(A, C) * B * D)
def test_series_expand():
"""Test series expension of commutator"""
hs = LocalSpace("0")
A = OperatorSymbol('A', hs=hs)
B = OperatorSymbol('B', hs=hs)
a3, a2, a1, a0, b3, b2, b1, b0, t, t0 = symbols(
'a_3, a_2, a_1, a_0, b_3, b_2, b_1, b_0, t, t_0')
A_form = (a3 * t**3 + a2 * t**2 + a1 * t + a0) * A
B_form = (b3 * t**3 + b2 * t**2 + b1 * t + b0) * B
comm = Commutator.create(A_form, B_form)
terms = comm.series_expand(t, 0, 2)
assert terms == (
a0 * b0 * Commutator(A, B),
(a0 * b1 + a1 * b0) * Commutator(A, B),
(a0 * b2 + a1 * b1 + a2 * b0) * Commutator(A, B),
)
A_form = (a1 * t + a0) * A
B_form = (b1 * t + b0) * B
comm = Commutator.create(A_form, B_form)
terms = comm.series_expand(t, t0, 1)
assert terms == (
((a0 * b0 + a0 * b1 * t0 + a1 * b0 * t0 + a1 * b1 * t0**2) *
Commutator(A, B)),
(a0 * b1 + a1 * b0 + 2 * a1 * b1 * t0) * Commutator(A, B),
)
comm = Commutator.create(A, B)
terms = comm.series_expand(t, t0, 1)
assert terms == (Commutator(A, B), ZeroOperator)
def test_exception_teardown():
"""Test that teardown works when breaking out due to an exception"""
class InstanceCachingException(Exception):
pass
h1 = LocalSpace("caching")
a = OperatorSymbol("a", hs=h1)
b = OperatorSymbol("b", hs=h1)
c = OperatorSymbol("c", hs=h1)
expr1 = a + b
instance_caching = Expression.instance_caching
try:
with no_instance_caching():
expr2 = a + c
raise InstanceCachingException
except InstanceCachingException:
expr3 = b + c
assert expr1 in OperatorPlus._instances.values()
assert expr2 not in OperatorPlus._instances.values()
assert expr3 in OperatorPlus._instances.values()
finally:
# Even if this failed we don't want to make a mess for other tests
Expression.instance_caching = instance_caching
instances = OperatorPlus._instances
try:
with temporary_instance_cache(OperatorPlus):
expr2 = a + c
raise InstanceCachingException
except InstanceCachingException:
assert expr1 in OperatorPlus._instances.values()
assert expr2 not in OperatorPlus._instances.values()
finally:
# Even if this failed we don't want to make a mess for other tests
OperatorPlus._instances = instances
