def _define(self):
"""Calculate a subcircuit that implements this unitary."""
if self.num_qubits == 1:
q = QuantumRegister(1, "q")
qc = QuantumCircuit(q, name=self.name)
theta, phi, lam, global_phase = _DECOMPOSER1Q.angles_and_phase(
self.to_matrix())
qc._append(U3Gate(theta, phi, lam), [q[0]], [])
qc.global_phase = global_phase
self.definition = qc
elif self.num_qubits == 2:
self.definition = two_qubit_cnot_decompose(self.to_matrix())
else:
q = QuantumRegister(self.num_qubits, "q")
qc = QuantumCircuit(q, name=self.name)
qc.append(isometry.Isometry(self.to_matrix(), 0, 0), qargs=q[:])
self.definition = qc
def control(self, num_ctrl_qubits=1, label=None, ctrl_state=None):
r"""Return controlled version of gate
Args:
num_ctrl_qubits (int): number of controls to add to gate (default=1)
label (str): optional gate label
ctrl_state (int or str or None): The control state in decimal or as a
bit string (e.g. '1011'). If None, use 2**num_ctrl_qubits-1.
Returns:
UnitaryGate: controlled version of gate.
Raises:
QiskitError: invalid ctrl_state
"""
cmat = _compute_control_matrix(self.to_matrix(), num_ctrl_qubits)
iso = isometry.Isometry(cmat, 0, 0)
return ControlledGate('c-unitary', self.num_qubits + num_ctrl_qubits, cmat,
definition=iso.definition, label=label)
def control(self, num_ctrl_qubits=1, label=None, ctrl_state=None):
r"""Return controlled version of gate
Args:
num_ctrl_qubits (int): number of controls to add to gate (default=1)
label (str): optional gate label
ctrl_state (int or str or None): The control state in decimal or as a
bit string (e.g. '1011'). If None, use 2**num_ctrl_qubits-1.
Returns:
UnitaryGate: controlled version of gate.
Raises:
QiskitError: Invalid ctrl_state.
ExtensionError: Non-unitary controlled unitary.
"""
cmat = _compute_control_matrix(self.to_matrix(),
num_ctrl_qubits,
ctrl_state=ctrl_state)
iso = isometry.Isometry(cmat, 0, 0)
cunitary = ControlledGate('c-unitary',
num_qubits=self.num_qubits + num_ctrl_qubits,
params=[cmat],
label=label,
num_ctrl_qubits=num_ctrl_qubits,
definition=iso.definition,
ctrl_state=ctrl_state)
from qiskit.quantum_info import Operator
# hack to correct global phase; should fix to prevent need for correction here
pmat = (Operator(iso.inverse()).data @ cmat)
diag = numpy.diag(pmat)
if not numpy.allclose(diag, diag[0]):
raise ExtensionError('controlled unitary generation failed')
phase = numpy.angle(diag[0])
if phase:
qreg = cunitary.definition.qregs[0]
cunitary.definition.u3(numpy.pi, phase, phase - numpy.pi, qreg[0])
cunitary.definition.u3(numpy.pi, 0, numpy.pi, qreg[0])
cunitary.base_gate = self.copy()
cunitary.base_gate.label = self.label
return cunitary
def control(self, num_ctrl_qubits=1, label=None, ctrl_state=None):
"""Return controlled version of gate
Args:
num_ctrl_qubits (int): number of controls to add to gate (default=1)
label (str): optional gate label
ctrl_state (int or str or None): The control state in decimal or as a
bit string (e.g. '1011'). If None, use 2**num_ctrl_qubits-1.
Returns:
UnitaryGate: controlled version of gate.
Raises:
QiskitError: Invalid ctrl_state.
ExtensionError: Non-unitary controlled unitary.
"""
mat = self.to_matrix()
cmat = _compute_control_matrix(mat, num_ctrl_qubits, ctrl_state=None)
iso = isometry.Isometry(cmat, 0, 0)
cunitary = ControlledGate(
"c-unitary",
num_qubits=self.num_qubits + num_ctrl_qubits,
params=[mat],
label=label,
num_ctrl_qubits=num_ctrl_qubits,
definition=iso.definition,
ctrl_state=ctrl_state,
base_gate=self.copy(),
)
from qiskit.quantum_info import Operator
# hack to correct global phase; should fix to prevent need for correction here
pmat = Operator(iso.inverse()).data @ cmat
diag = numpy.diag(pmat)
if not numpy.allclose(diag, diag[0]):
raise ExtensionError("controlled unitary generation failed")
phase = numpy.angle(diag[0])
if phase:
# need to apply to _definition since open controls creates temporary definition
cunitary._definition.global_phase = phase
return cunitary
def run(self, dag: DAGCircuit) -> DAGCircuit:
"""Run the UnitarySynthesis pass on `dag`.
Args:
dag: input dag.
Returns:
Output dag with UnitaryGates synthesized to target basis.
"""
euler_basis = _choose_euler_basis(self._basis_gates)
kak_gate = _choose_kak_gate(self._basis_gates)
decomposer1q, decomposer2q = None, None
if euler_basis is not None:
decomposer1q = one_qubit_decompose.OneQubitEulerDecomposer(
euler_basis)
if kak_gate is not None:
decomposer2q = TwoQubitBasisDecomposer(kak_gate,
euler_basis=euler_basis)
for node in dag.named_nodes("unitary"):
synth_dag = None
if len(node.qargs) == 1:
if decomposer1q is None:
continue
synth_dag = circuit_to_dag(
decomposer1q._decompose(node.op.to_matrix()))
elif len(node.qargs) == 2:
if decomposer2q is None:
continue
synth_dag = circuit_to_dag(
decomposer2q(node.op.to_matrix(),
basis_fidelity=self._approximation_degree))
else:
synth_dag = circuit_to_dag(
isometry.Isometry(node.op.to_matrix(), 0, 0).definition)
dag.substitute_node_with_dag(node, synth_dag)
return dag
