CommutativeCancellation

class qiskit.transpiler.passes.CommutativeCancellation(*args, **kwargs)[source]

Bases: TransformationPass

Cancel the redundant (self-adjoint) gates through commutation relations.

Pass for cancelling self-inverse gates/rotations. The cancellation utilizes the commutation relations in the circuit. Gates considered include:

H, X, Y, Z, CX, CY, CZ

CommutativeCancellation initializer.

Parameters:

  • basis_gates (list[str]) – Basis gates to consider, e.g. ['u3', 'cx']. For the effects of this pass, the basis is the set intersection between the basis_gates parameter and the gates in the dag.

  • target (Target) – The Target representing the target backend, if both basis_gates and target are specified then this argument will take precedence and basis_gates will be ignored.

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

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, qiskit.passmanager.compilation_status.PassManagerState]

name()

Name of the pass.

Return type:

str

run(dag)[source]

Run the CommutativeCancellation pass on dag.

Parameters:

dag (DAGCircuit) – the DAG to be optimized.

Returns:

the optimized DAG.

Return type:

DAGCircuit

Raises:

TranspilerError – when the 1-qubit rotation gates are not found

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