def _xx_interaction_via_full_czs(q0: 'cirq.Qid', q1: 'cirq.Qid', x: float):
a = x * -2 / np.pi
yield ops.H(q1)
yield ops.CZ(q0, q1)
yield ops.X(q0)**a
yield ops.CZ(q0, q1)
yield ops.H(q1)
def _xx_interaction_via_full_czs(q0: ops.QubitId, q1: ops.QubitId, x: float):
a = x * -2 / np.pi
yield ops.H(q1)
yield ops.CZ(q0, q1)
yield ops.X(q0)**a
yield ops.CZ(q0, q1)
yield ops.H(q1)
def test_moment_by_moment_schedule_device_validation_fails():
device = _TestDevice()
qubits = device.qubits
circuit = Circuit(
[Moment([ops.CZ(qubits[0], qubits[1]),
ops.CZ(qubits[2], qubits[3])])])
with pytest.raises(ValueError, match="Adjacent CZ"):
_ = moment_by_moment_schedule(device, circuit)
def test_ignores_2qubit_target():
m = MergeRotations(0.000001)
q = ops.QubitId()
q2 = ops.QubitId()
c = circuits.Circuit([
circuits.Moment([ops.CZ(q, q2)]),
])
m.optimization_at(c, 0, c.operation_at(q, 0))
assert c == circuits.Circuit([circuits.Moment([ops.CZ(q, q2)])])
def test_czs_separated_by_single_gates_correct():
q0 = ops.QubitId()
q1 = ops.QubitId()
assert_optimization_not_broken(
circuits.Circuit.from_ops(
ops.CZ(q0, q1),
ops.X(q1),
ops.X(q1),
ops.X(q1),
ops.CZ(q0, q1),
))
def test_moment_by_moment_schedule_moment_of_two_qubit_ops():
device = _TestDevice()
qubits = device.qubits
circuit = Circuit(
[Moment((ops.CZ(qubits[i], qubits[i + 1]) for i in range(0, 9, 3)))])
schedule = moment_by_moment_schedule(device, circuit)
zero_ns = cirq.Timestamp()
expected = set(
ScheduledOperation.op_at_on(ops.CZ(qubits[i], qubits[i + 1]), zero_ns,
device) for i in range(0, 9, 3))
assert set(schedule.scheduled_operations) == expected
def _xx_yy_interaction_via_full_czs(q0: 'cirq.Qid', q1: 'cirq.Qid', x: float, y: float):
a = x * -2 / np.pi
b = y * -2 / np.pi
yield ops.X(q0) ** 0.5
yield ops.H(q1)
yield ops.CZ(q0, q1)
yield ops.H(q1)
yield ops.X(q0) ** a
yield ops.Y(q1) ** b
yield ops.H(q1)
yield ops.CZ(q0, q1)
yield ops.H(q1)
yield ops.X(q0) ** -0.5
def test_interchangeable_qubit_eq():
a = ops.NamedQubit('a')
b = ops.NamedQubit('b')
c = ops.NamedQubit('c')
eq = EqualsTester()
eq.add_equality_group(ops.SWAP(a, b), ops.SWAP(b, a))
eq.add_equality_group(ops.SWAP(a, c))
eq.add_equality_group(ops.CZ(a, b), ops.CZ(b, a))
eq.add_equality_group(ops.CZ(a, c))
eq.add_equality_group(ops.CNOT(a, b))
eq.add_equality_group(ops.CNOT(b, a))
eq.add_equality_group(ops.CNOT(a, c))
def xmon_op_from_proto(proto: operations_pb2.Operation) -> 'cirq.Operation':
"""Convert the proto to the corresponding operation.
See protos in api/google/v1 for specification of the protos.
Args:
proto: Operation proto.
Returns:
The operation.
"""
param = _parameterized_value_from_proto
qubit = _qubit_from_proto
if proto.HasField('exp_w'):
exp_w = proto.exp_w
return ops.PhasedXPowGate(
exponent=param(exp_w.half_turns),
phase_exponent=param(exp_w.axis_half_turns),
).on(qubit(exp_w.target))
if proto.HasField('exp_z'):
exp_z = proto.exp_z
return ops.Z(qubit(exp_z.target))**param(exp_z.half_turns)
if proto.HasField('exp_11'):
exp_11 = proto.exp_11
return ops.CZ(qubit(exp_11.target1),
qubit(exp_11.target2))**param(exp_11.half_turns)
if proto.HasField('measurement'):
meas = proto.measurement
return ops.MeasurementGate(num_qubits=len(meas.targets),
key=meas.key,
invert_mask=tuple(meas.invert_mask)).on(
*[qubit(q) for q in meas.targets])
raise ValueError(f'invalid operation: {proto}')
def controlled_op_to_operations(control: ops.QubitId,
target: ops.QubitId,
operation: np.ndarray,
tolerance: float = 0.0) -> List[ops.Operation]:
"""Decomposes a controlled single-qubit operation into Z/XY/CZ gates.
Args:
control: The control qubit.
target: The qubit to apply an operation to, when the control is on.
operation: The single-qubit operation being controlled.
tolerance: A limit on the amount of error introduced by the
construction.
Returns:
A list of Operations that apply the controlled operation.
"""
u, z_phase, global_phase = single_qubit_op_to_framed_phase_form(operation)
if abs(z_phase - 1) <= tolerance:
return []
u_gates = single_qubit_matrix_to_gates(u, tolerance)
if u_gates and isinstance(u_gates[-1], ops.ZPowGate):
# Don't keep border operations that commute with CZ.
del u_gates[-1]
ops_before = [gate(target) for gate in u_gates]
ops_after = protocols.inverse(ops_before)
effect = ops.CZ(control, target)**(cmath.phase(z_phase) / math.pi)
kickback = ops.Z(control)**(cmath.phase(global_phase) / math.pi)
return list(
ops.flatten_op_tree(
(ops_before, effect,
kickback if abs(global_phase - 1) > tolerance else [],
ops_after)))
def test_teleportation_diagram():
ali = ops.NamedQubit('alice')
car = ops.NamedQubit('carrier')
bob = ops.NamedQubit('bob')
circuit = Circuit.from_ops(
ops.H(car),
ops.CNOT(car, bob),
ops.X(ali)**0.5,
ops.CNOT(ali, car),
ops.H(ali),
[ops.measure(ali), ops.measure(car)],
ops.CNOT(car, bob),
ops.CZ(ali, bob))
diagram = circuit_to_latex_using_qcircuit(
circuit,
qubit_order=ops.QubitOrder.explicit([ali, car, bob]))
assert diagram.strip() == """
\\Qcircuit @R=1em @C=0.75em { \\\\
\\lstick{\\text{alice}}& \\qw &\\qw & \\gate{\\text{X}^{0.5}} \\qw & \\control \\qw & \\gate{\\text{H}} \\qw & \\meter \\qw &\\qw & \\control \\qw &\\qw\\\\
\\lstick{\\text{carrier}}& \\qw & \\gate{\\text{H}} \\qw & \\control \\qw & \\targ \\qw \\qwx &\\qw & \\meter \\qw & \\control \\qw &\\qw \\qwx &\\qw\\\\
\\lstick{\\text{bob}}& \\qw &\\qw & \\targ \\qw \\qwx &\\qw &\\qw &\\qw & \\targ \\qw \\qwx & \\control \\qw \\qwx &\\qw \\\\
\\\\ }
""".strip()
def _decompose_(self, qubits):
"""
Implements the decomposition of Draper provided in https://arxiv.org/pdf/quant-ph/0008033.pdf
Args:
qubits: |qubits| = 2 * self.size_of_inputs, in order a0 a1 ... an b0 b1 ... bn
"""
# For slicing
qubits = list(qubits)
assert len(
qubits
) == 2 * self._size_of_inputs, f'A and B must be of the same length.'
# A and B register appear in order
A = qubits[:self._size_of_inputs]
B = qubits[self._size_of_inputs:][::-1]
yield self._apply_qft(A)
A = A[::-1]
for i in range(self._size_of_inputs):
for j in range(i, self._size_of_inputs):
yield ops.CZ(B[j], A[j - i])**(2 * 1 / (2**(i + 1)))
A = A[::-1]
yield cirq.inverse(self._apply_qft(A))
def test_from_braket_non_parameterized_two_qubit_gates():
braket_circuit = BKCircuit()
instructions = [
Instruction(braket_gates.CNot(), target=[2, 3]),
Instruction(braket_gates.Swap(), target=[3, 4]),
Instruction(braket_gates.ISwap(), target=[2, 3]),
Instruction(braket_gates.CZ(), target=(3, 4)),
Instruction(braket_gates.CY(), target=(2, 3)),
]
for instr in instructions:
braket_circuit.add_instruction(instr)
cirq_circuit = from_braket(braket_circuit)
qreg = LineQubit.range(2, 5)
expected_cirq_circuit = Circuit(
ops.CNOT(*qreg[:2]),
ops.SWAP(*qreg[1:]),
ops.ISWAP(*qreg[:2]),
ops.CZ(*qreg[1:]),
ops.ControlledGate(ops.Y).on(*qreg[:2]),
)
assert np.allclose(
protocols.unitary(cirq_circuit),
protocols.unitary(expected_cirq_circuit),
)
def test_controlled_op_to_gates_omits_negligible_global_phase():
qc = ops.QubitId()
qt = ops.QubitId()
operations = decompositions.controlled_op_to_native_gates(
control=qc, target=qt, operation=ops.H.matrix(), tolerance=0.0001)
assert operations == [ops.Y(qt)**-0.25, ops.CZ(qc, qt), ops.Y(qt)**0.25]
def test_qubits():
a = ops.QubitId()
b = ops.QubitId()
assert Moment([ops.X(a), ops.X(b)]).qubits == {a , b}
assert Moment([ops.X(a)]).qubits == {a}
assert Moment([ops.CZ(a, b)]).qubits == {a, b}
def test_copy():
a = ops.QubitId()
b = ops.QubitId()
original = Moment([ops.CZ(a, b)])
copy = original.__copy__()
assert original == copy
assert id(original) != id(copy)
def _parity_interaction(q0: 'cirq.Qid',
q1: 'cirq.Qid',
rads: float,
atol: float,
gate: Optional[ops.Gate] = None):
"""Yields a ZZ interaction framed by the given operation."""
if abs(rads) < atol:
return
h = rads * -2 / np.pi
if gate is not None:
g = cast(ops.Gate, gate)
yield g.on(q0), g.on(q1)
# If rads is ±pi/4 radians within tolerance, single full-CZ suffices.
if _is_trivial_angle(rads, atol):
yield ops.CZ.on(q0, q1)
else:
yield ops.CZ(q0, q1)**(-2 * h)
yield ops.Z(q0)**h
yield ops.Z(q1)**h
if gate is not None:
g = protocols.inverse(gate)
yield g.on(q0), g.on(q1)
def test_ignores_czs_separated_by_parameterized():
q0 = ops.QubitId()
q1 = ops.QubitId()
assert_optimizes(
before=circuits.Circuit([
circuits.Moment([ops.CZ(q0, q1)]),
circuits.Moment([ExpZGate(
half_turns=Symbol('boo'))(q0)]),
circuits.Moment([ops.CZ(q0, q1)]),
]),
after=circuits.Circuit([
circuits.Moment([ops.CZ(q0, q1)]),
circuits.Moment([ExpZGate(
half_turns=Symbol('boo'))(q0)]),
circuits.Moment([ops.CZ(q0, q1)]),
]))
def _parity_interaction(q0: ops.QubitId,
q1: ops.QubitId,
rads: float,
tolerance: float,
gate: Optional[ops.ReversibleEffect] = None):
"""Yields a ZZ interaction framed by the given operation."""
if abs(rads) < tolerance:
return
h = rads * -2 / np.pi
if gate is not None:
g = cast(ops.Gate, gate)
yield g.on(q0), g.on(q1)
# If rads is ±pi/4 radians within tolerance, single full-CZ suffices.
if _is_trivial_angle(rads, tolerance):
yield ops.CZ.on(q0, q1)
else:
yield ops.CZ(q0, q1)**(-2 * h)
yield ops.Z(q0)**h
yield ops.Z(q1)**h
if gate is not None:
g = cast(ops.Gate, gate.inverse())
yield g.on(q0), g.on(q1)
def xmon_op_from_proto_dict(proto_dict: Dict) -> 'cirq.Operation':
"""Convert the proto dictionary to the corresponding operation.
See protos in api/google/v1 for specification of the protos.
Args:
proto_dict: Dictionary representing the proto. Keys are always
strings, but values may be types correspond to a raw proto type
or another dictionary (for messages).
Returns:
The operation.
Raises:
ValueError if the dictionary does not contain required values
corresponding to the proto.
"""
def raise_missing_fields(gate_name: str):
raise ValueError('{} missing required fields: {}'.format(
gate_name, proto_dict))
param = _parameterized_value_from_proto_dict
qubit = _qubit_from_proto_dict
if 'exp_w' in proto_dict:
exp_w = proto_dict['exp_w']
if ('half_turns' not in exp_w or 'axis_half_turns' not in exp_w
or 'target' not in exp_w):
raise_missing_fields('ExpW')
return ops.PhasedXPowGate(
exponent=param(exp_w['half_turns']),
phase_exponent=param(exp_w['axis_half_turns']),
).on(qubit(exp_w['target']))
if 'exp_z' in proto_dict:
exp_z = proto_dict['exp_z']
if 'half_turns' not in exp_z or 'target' not in exp_z:
raise_missing_fields('ExpZ')
return ops.Z(qubit(exp_z['target']))**param(exp_z['half_turns'])
if 'exp_11' in proto_dict:
exp_11 = proto_dict['exp_11']
if ('half_turns' not in exp_11 or 'target1' not in exp_11
or 'target2' not in exp_11):
raise_missing_fields('Exp11')
return ops.CZ(qubit(exp_11['target1']),
qubit(exp_11['target2']))**param(exp_11['half_turns'])
if 'measurement' in proto_dict:
meas = proto_dict['measurement']
invert_mask = cast(Tuple[Any, ...], ())
if 'invert_mask' in meas:
invert_mask = tuple(
_load_json_bool(x) for x in meas['invert_mask'])
if 'key' not in meas or 'targets' not in meas:
raise_missing_fields('Measurement')
return ops.MeasurementGate(
num_qubits=len(meas['targets']),
key=meas['key'],
invert_mask=invert_mask).on(*[qubit(q) for q in meas['targets']])
raise ValueError('invalid operation: {}'.format(proto_dict))
def test_operates_on():
a = ops.QubitId()
b = ops.QubitId()
c = ops.QubitId()
# Empty case.
assert not Moment().operates_on([])
assert not Moment().operates_on([a])
assert not Moment().operates_on([b])
assert not Moment().operates_on([a, b])
# One-qubit operation case.
assert not Moment([ops.X(a)]).operates_on([])
assert Moment([ops.X(a)]).operates_on([a])
assert not Moment([ops.X(a)]).operates_on([b])
assert Moment([ops.X(a)]).operates_on([a, b])
# Two-qubit operation case.
assert not Moment([ops.CZ(a, b)]).operates_on([])
assert Moment([ops.CZ(a, b)]).operates_on([a])
assert Moment([ops.CZ(a, b)]).operates_on([b])
assert Moment([ops.CZ(a, b)]).operates_on([a, b])
assert not Moment([ops.CZ(a, b)]).operates_on([c])
assert Moment([ops.CZ(a, b)]).operates_on([a, c])
assert Moment([ops.CZ(a, b)]).operates_on([a, b, c])
# Multiple operations case.
assert not Moment([ops.X(a), ops.X(b)]).operates_on([])
assert Moment([ops.X(a), ops.X(b)]).operates_on([a])
assert Moment([ops.X(a), ops.X(b)]).operates_on([b])
assert Moment([ops.X(a), ops.X(b)]).operates_on([a, b])
assert not Moment([ops.X(a), ops.X(b)]).operates_on([c])
assert Moment([ops.X(a), ops.X(b)]).operates_on([a, c])
assert Moment([ops.X(a), ops.X(b)]).operates_on([a, b, c])
def _apply_qft(register):
"""
applies the qft to the register according to https://arxiv.org/pdf/quant-ph/0008033.pdf
"""
rreg = register[::-1]
for i, q in enumerate(rreg):
yield ops.H(q)
for j in range(i + 1, len(rreg)):
yield ops.CZ(rreg[j], q)**(2 * 1 / (2**(j + 1)))
def _xx_yy_zz_interaction_via_full_czs(q0: 'cirq.Qid', q1: 'cirq.Qid',
x: float, y: float, z: float):
a = x * -2 / np.pi + 0.5
b = y * -2 / np.pi + 0.5
c = z * -2 / np.pi + 0.5
yield ops.X(q0)**0.5
yield ops.H(q1)
yield ops.CZ(q0, q1)
yield ops.H(q1)
yield ops.X(q0)**a
yield ops.Y(q1)**b
yield ops.H.on(q0)
yield ops.CZ(q1, q0)
yield ops.H(q0)
yield ops.X(q1)**-0.5
yield ops.Z(q1)**c
yield ops.H(q1)
yield ops.CZ(q0, q1)
yield ops.H(q1)
def test_moment_by_moment_schedule_max_duration():
device = _TestDevice()
qubits = device.qubits
circuit = Circuit([
Moment([ops.H(qubits[0]),
ops.CZ(qubits[1], qubits[2])]),
Moment([ops.H(qubits[0])])
])
schedule = moment_by_moment_schedule(device, circuit)
zero_ns = cirq.Timestamp()
fourty_ns = cirq.Timestamp(nanos=40)
assert set(schedule.scheduled_operations) == {
ScheduledOperation.op_at_on(ops.H(qubits[0]), zero_ns, device),
ScheduledOperation.op_at_on(ops.CZ(qubits[1], qubits[2]), zero_ns,
device),
ScheduledOperation.op_at_on(ops.H(qubits[0]), fourty_ns, device),
}
def test_moment_by_moment_schedule_two_moments():
device = _TestDevice()
qubits = device.qubits
circuit = Circuit([
Moment(ops.H(q) for q in qubits),
Moment((ops.CZ(qubits[i], qubits[i + 1]) for i in range(0, 9, 3)))
])
schedule = moment_by_moment_schedule(device, circuit)
zero_ns = cirq.Timestamp()
twenty_ns = cirq.Timestamp(nanos=20)
expected_one_qubit = set(
ScheduledOperation.op_at_on(ops.H(q), zero_ns, device) for q in qubits)
expected_two_qubit = set(
ScheduledOperation.op_at_on(ops.CZ(qubits[i], qubits[i + 1]),
twenty_ns, device) for i in range(0, 9, 3))
expected = expected_one_qubit.union(expected_two_qubit)
assert set(schedule.scheduled_operations) == expected
def decompose_keep_func(self, op: ops.Operation) -> bool:
# Keep CZs.
if len(op.qubits) == 2 and op == ops.CZ(*op.qubits):
return True
# Keep within-group operation with a known unitary
if self.all_in_same_group(*op.qubits):
if protocols.unitary(op, None) is not None:
return True
return False
def test_text_diagrams():
a = ops.NamedQubit('a')
b = ops.NamedQubit('b')
circuit = Circuit.from_ops(ops.SWAP(a, b), ops.X(a), ops.Y(a), ops.Z(a),
ops.CZ(a, b), ops.CNOT(a, b), ops.CNOT(b, a),
ops.H(a))
assert circuit.to_text_diagram().strip() == """
a: ───×───X───Y───Z───@───@───X───H───
│ │ │ │
b: ───×───────────────@───X───@───────
""".strip()
def _easy_direction_partial_cz(q0: ops.QubitId, q1: ops.QubitId, t: float):
"""The actual hardware can only do CZs that phase counter-clockwise.
This method replaces clockwise phase(t) to counter-clockwise.
Args:
q0: The first qubit being operated on.
q1: The other qubit being operated on.
t: The parameter to describe partial-CZ(CZ^t).
Yields:
Yields an equivalent circuit for CZ^t with counter-clock phased CZs.
"""
if t >= 0:
yield ops.CZ(q0, q1)**t
return
yield ops.Z(q0)**t
yield ops.X(q1)
yield ops.CZ(q0, q1)**(-t)
yield ops.X(q1)
def test_validation():
a = ops.QubitId()
b = ops.QubitId()
c = ops.QubitId()
d = ops.QubitId()
_ = Moment([])
_ = Moment([ops.X(a)])
_ = Moment([ops.CZ(a, b)])
_ = Moment([ops.CZ(b, d)])
_ = Moment([ops.CZ(a, b), ops.CZ(c, d)])
_ = Moment([ops.CZ(a, c), ops.CZ(b, d)])
_ = Moment([ops.CZ(a, c), ops.X(b)])
with pytest.raises(ValueError):
_ = Moment([ops.X(a), ops.X(a)])
with pytest.raises(ValueError):
_ = Moment([ops.CZ(a, c), ops.X(c)])
with pytest.raises(ValueError):
_ = Moment([ops.CZ(a, c), ops.CZ(c, d)])
def test_clears_known_empties_even_at_zero_tolerance():
m = circuits.DropNegligible(0.001)
q = ops.QubitId()
q2 = ops.QubitId()
c = circuits.Circuit.from_ops(
ops.Z(q)**0,
ops.Y(q)**0.0000001,
ops.X(q)**-0.0000001,
ops.CZ(q, q2)**0)
m.optimize_circuit(c)
assert c == circuits.Circuit([circuits.Moment()] * 4)