InverseCancellation

class qiskit.transpiler.passes.InverseCancellation(*args, **kwargs)

GitHub

Bases: TransformationPass

Cancel specific Gates which are inverses of each other when they occur back-to- back.

Initialize InverseCancellation pass.

Parameters

gates_to_cancel –

List describing the gates to cancel. Each element of the list is either a single gate or a pair of gates. If a single gate, then it should be self-inverse. If a pair of gates, then the gates in the pair should be inverses of each other. If None a default list of self-inverse gates and a default list of inverse gate pairs will be used. The current default list of self-inverse gates is:
- CXGate
- ECRGate
- CYGate
- CZGate
- XGate
- YGate
- ZGate
- HGate
- SwapGate
- CHGate
- CCXGate
- CCZGate
- RCCXGate
- CSwapGate
- C3XGate
and the default list of inverse gate pairs is:
- TGate and TdgGate
- SGate and SdgGate
- SXGate and SXdgGate
- CSGate and CSdgGate
run_default – If set to true and gates_to_cancel is set to a list then in addition to the gates listed in gates_to_cancel the default list of gate inverses (the same as when gates_to_cancel is set to None) will be run. The order of evaluation is significant in how sequences of gates are cancelled and the default gates will be evaluated after the provided gates in gates_to_cancel. If gates_to_cancel is None this option has no impact.

Raises

TranspilerError – Input is not a self-inverse gate or a pair of inverse 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

execute

execute(passmanager_ir, state, callback=None)

GitHub

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.