ConvertISAToClifford¶

class ConvertISAToClifford(*args, **kwargs)[source]¶

Bases: TransformationPass

Convert the gates of an ISA circuit to Clifford gates.

ISA circuits only contain Clifford gates from a restricted set or qiskit.circuit.library.RZGates by arbitrary angles. To convert them to Clifford circuits, this pass rounds the angle of every qiskit.circuit.library.RZGate or qiskit.circuit.library.RZZGate or qiskit.circuit.library.RXGate to the closest multiple of pi/2 (or to a random multiple of pi/2 if the angle is unspecified), while it skips every Clifford gate, measurement, and barrier.

import numpy as np

from qiskit.circuit import QuantumCircuit, Parameter
from qiskit.transpiler import PassManager

from qiskit_ibm_runtime.transpiler.passes import ConvertISAToClifford

# An ISA circuit ending with a Z rotation by pi/3
qc = QuantumCircuit(2, 2)
qc.sx(0)
qc.rz(np.pi/2, 0)
qc.sx(0)
qc.barrier()
qc.cx(0, 1)
qc.rz(np.pi/3, 0)  # non-Clifford Z rotation
qc.rz(Parameter("th"), 0)  # Z rotation with unspecified angle

# Turn into a Clifford circuit
pm = PassManager([ConvertISAToClifford()])
clifford_qc = pm.run(qc)

Raises:: ValueError – If the given circuit contains unsupported operations, such as non-ISA gates.

Attributes

is_analysis_pass¶

Check if the pass is an analysis pass.

If the pass is an AnalysisPass, that means that the pass can analyze the DAG and write the results of that analysis in the property set. Modifications on the DAG are not allowed by this kind of pass.

is_transformation_pass¶

Check if the pass is a transformation pass.

If the pass is a TransformationPass, that means that the pass can manipulate the DAG, but cannot modify the property set (but it can be read).

Methods

__call__(circuit, property_set=None)¶

Runs the pass on circuit.

Parameters:

circuit (QuantumCircuit) – The dag on which the pass is run.
property_set (PropertySet | dict | None) – Input/output property set. An analysis pass might change the property set in-place. If not given, the existing property_set attribute of the pass will be used (if set).

Returns:

If on transformation pass, the resulting QuantumCircuit. If analysis pass, the input circuit.

Return type:

QuantumCircuit

execute(passmanager_ir, state, callback=None)¶

Execute optimization task for input Qiskit IR.

Parameters:

passmanager_ir (Any) – Qiskit IR to optimize.
state (PassManagerState) – State associated with workflow execution by the pass manager itself.
callback (Callable | None) – A callback function which is caller per execution of optimization task.

Returns:

Optimized Qiskit IR and state of the workflow.

Return type:

tuple[Any, PassManagerState]

name()¶

Name of the pass.

Return type:: str

run(dag)[source]¶

Run a pass on the DAGCircuit. This is implemented by the pass developer.

Parameters:: dag (DAGCircuit) – the dag on which the pass is run.
Raises:: NotImplementedError – when this is left unimplemented for a pass.
Return type:: DAGCircuit

update_status(state, run_state)¶

Update workflow status.

Parameters:

state (PassManagerState) – Pass manager state to update.
run_state (RunState) – Completion status of current task.

Returns:

Updated pass manager state.

Return type:

PassManagerState