def test_circuit_from_quil():
q0, q1, q2 = LineQubit.range(3)
cirq_circuit = Circuit([
I(q0),
I(q1),
I(q2),
X(q0),
Y(q1),
Z(q2),
H(q0),
S(q1),
T(q2),
Z(q0)**(1 / 8),
Z(q1)**(1 / 8),
Z(q2)**(1 / 8),
rx(np.pi / 2)(q0),
ry(np.pi / 2)(q1),
rz(np.pi / 2)(q2),
CZ(q0, q1),
CNOT(q1, q2),
cphase(np.pi / 2)(q0, q1),
cphase00(np.pi / 2)(q1, q2),
cphase01(np.pi / 2)(q0, q1),
cphase10(np.pi / 2)(q1, q2),
ISWAP(q0, q1),
pswap(np.pi / 2)(q1, q2),
SWAP(q0, q1),
xy(np.pi / 2)(q1, q2),
CCNOT(q0, q1, q2),
CSWAP(q0, q1, q2),
MeasurementGate(1, key="ro[0]")(q0),
MeasurementGate(1, key="ro[1]")(q1),
MeasurementGate(1, key="ro[2]")(q2),
])
# build the same Circuit, using Quil
quil_circuit = circuit_from_quil(QUIL_PROGRAM)
# test Circuit equivalence
assert cirq_circuit == quil_circuit
pyquil_circuit = Program(QUIL_PROGRAM)
# drop declare and measures, get Program unitary
pyquil_unitary = program_unitary(pyquil_circuit[1:-3], n_qubits=3)
# fix qubit order convention
cirq_circuit_swapped = Circuit(SWAP(q0, q2), cirq_circuit[:-1],
SWAP(q0, q2))
# get Circuit unitary
cirq_unitary = cirq_circuit_swapped.unitary()
# test unitary equivalence
assert np.isclose(pyquil_unitary, cirq_unitary).all()
def circuit_from_quil(quil: str) -> Circuit:
"""Convert a Quil program to a Cirq Circuit.
Args:
quil: The Quil program to convert.
Returns:
A Cirq Circuit generated from the Quil program.
Raises:
UnsupportedQuilInstruction: Cirq does not support the specified Quil instruction.
UndefinedQuilGate: Cirq does not support the specified Quil gate.
References:
https://github.com/rigetti/pyquil
"""
circuit = Circuit()
defined_gates = SUPPORTED_GATES.copy()
instructions = parse(quil)
for inst in instructions:
# Add DEFGATE-defined gates to defgates dict using MatrixGate.
if isinstance(inst, DefGate):
if inst.parameters:
raise UnsupportedQuilInstruction(
"Parameterized DEFGATEs are currently unsupported.")
defined_gates[inst.name] = MatrixGate(inst.matrix)
# Pass when encountering a DECLARE.
elif isinstance(inst, Declare):
pass
# Convert pyQuil gates to Cirq operations.
elif isinstance(inst, PyQuilGate):
quil_gate_name = inst.name
quil_gate_params = inst.params
line_qubits = list(LineQubit(q.index) for q in inst.qubits)
if quil_gate_name not in defined_gates:
raise UndefinedQuilGate(
f"Quil gate {quil_gate_name} not supported in Cirq.")
cirq_gate_fn = defined_gates[quil_gate_name]
if quil_gate_params:
circuit += cirq_gate_fn(*quil_gate_params)(*line_qubits)
else:
circuit += cirq_gate_fn(*line_qubits)
# Convert pyQuil MEASURE operations to Cirq MeasurementGate objects.
elif isinstance(inst, PyQuilMeasurement):
line_qubit = LineQubit(inst.qubit.index)
if inst.classical_reg is None:
raise UnsupportedQuilInstruction(
f"Quil measurement {inst} without classical register "
f"not currently supported in Cirq.")
quil_memory_reference = inst.classical_reg.out()
circuit += MeasurementGate(1,
key=quil_memory_reference)(line_qubit)
# Raise a targeted error when encountering a PRAGMA.
elif isinstance(inst, Pragma):
raise UnsupportedQuilInstruction(PRAGMA_ERROR)
# Raise a targeted error when encountering a RESET.
elif isinstance(inst, (Reset, ResetQubit)):
raise UnsupportedQuilInstruction(RESET_ERROR)
# Raise a general error when encountering an unconsidered type.
else:
raise UnsupportedQuilInstruction(
f"Quil instruction {inst} of type {type(inst)} not currently supported in Cirq."
)
return circuit