def dagdependency_to_dag(dagdependency):
"""Build a ``DAGCircuit`` object from a ``DAGDependency``.
Args:
dag dependency (DAGDependency): the input dag.
Return:
DAGCircuit: the DAG representing the input circuit.
"""
dagcircuit = DAGCircuit()
dagcircuit.name = dagdependency.name
qregs = list(dagdependency.qregs.values())
cregs = list(dagdependency.cregs.values())
for register in qregs:
dagcircuit.add_qreg(register)
for register in cregs:
dagcircuit.add_creg(register)
for node in dagdependency.get_nodes():
# Get arguments for classical control (if any)
inst = node.op.copy()
inst.condition = node.condition
dagcircuit.apply_operation_back(inst, node.qargs, node.cargs,
inst.condition)
# copy metadata
dagcircuit.global_phase = dagdependency.global_phase
dagcircuit.calibrations = dagdependency.calibrations
return dagcircuit
def circuit_to_dag(circuit):
"""Build a ``DAGCircuit`` object from a ``QuantumCircuit``.
Args:
circuit (QuantumCircuit): the input circuit.
Return:
DAGCircuit: the DAG representing the input circuit.
Example:
.. jupyter-execute::
from qiskit import QuantumRegister, ClassicalRegister, QuantumCircuit
from qiskit.dagcircuit import DAGCircuit
from qiskit.converters import circuit_to_dag
from qiskit.visualization import dag_drawer
%matplotlib inline
q = QuantumRegister(3, 'q')
c = ClassicalRegister(3, 'c')
circ = QuantumCircuit(q, c)
circ.h(q[0])
circ.cx(q[0], q[1])
circ.measure(q[0], c[0])
circ.rz(0.5, q[1]).c_if(c, 2)
dag = circuit_to_dag(circ)
dag_drawer(dag)
"""
dagcircuit = DAGCircuit()
dagcircuit.name = circuit.name
dagcircuit.global_phase = circuit.global_phase
dagcircuit.calibrations = circuit.calibrations
dagcircuit.metadata = circuit.metadata
dagcircuit.add_qubits(circuit.qubits)
dagcircuit.add_clbits(circuit.clbits)
for register in circuit.qregs:
dagcircuit.add_qreg(register)
for register in circuit.cregs:
dagcircuit.add_creg(register)
for instruction in circuit.data:
dagcircuit.apply_operation_back(instruction.operation.copy(),
instruction.qubits, instruction.clbits)
dagcircuit.duration = circuit.duration
dagcircuit.unit = circuit.unit
return dagcircuit