qiskit.transpiler.passes.DenseLayout

class DenseLayout(*args, **kwargs)

Choose a Layout by finding the most connected subset of qubits.

This pass associates a physical qubit (int) to each virtual qubit of the circuit (Qubit).

Note

Even though a ‘layout’ is not strictly a property of the DAG, in the transpiler architecture it is best passed around between passes by being set in property_set.

DenseLayout initializer.

Parameters

• coupling_map (Coupling) – directed graph representing a coupling map.

• backend_prop (BackendProperties) – backend properties object

__init__(coupling_map, backend_prop=None)

DenseLayout initializer.

Parameters

• coupling_map (Coupling) – directed graph representing a coupling map.

• backend_prop (BackendProperties) – backend properties object

Methods

__init__(coupling_map[, backend_prop])	DenseLayout initializer.
name()	Return the name of the pass.
run(dag)	Run the DenseLayout pass on dag.

Attributes

is_analysis_pass	Check if the pass is an analysis pass.
is_transformation_pass	Check if the pass is a transformation pass.

property 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.

property 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).

name()

Return the name of the pass.

run(dag)

Run the DenseLayout pass on dag.

Pick a convenient layout depending on the best matching qubit connectivity, and set the property layout.

Parameters

dag (DAGCircuit) – DAG to find layout for.

Raises

TranspilerError – if dag wider than self.coupling_map