pytket.mapping

The mapping module provides an API to interact with the MappingManager class, with methods for mapping logical circuits to physical circuits and for defining custom routing solutions.

class pytket.mapping.AASLabellingMethod

Defines a Labeling Method for aas for labelling all unplaced qubits in a circuit

__init__(self) → None

AASLabellingMethod constructor.

class pytket.mapping.AASRouteRoutingMethod

Defines a RoutingMethod object for mapping circuits that uses the architecture aware synthesis method implemented in tket.

__init__(self, aaslookahead: int) → None

AASRouteRoutingMethod constructor.

Parameters:

aaslookahead – recursive interation depth of the architecture aware synthesis.method.

class pytket.mapping.BoxDecompositionRoutingMethod

Defines a RoutingMethod object for decomposing boxes.

__init__(self) → None

BoxDecompositionRoutingMethod constructor.

class pytket.mapping.LexiLabellingMethod

Defines a RoutingMethod for labelling Qubits that uses the Lexicographical Comparison approach outlined in arXiv:1902.08091.

__init__(self) → None

LexiLabellingMethod constructor.

class pytket.mapping.LexiRouteRoutingMethod

Defines a RoutingMethod object for mapping circuits that uses the Lexicographical Comparison approach outlined in arXiv:1902.08091.Only supports 1-qubit, 2-qubit and barrier gates.

__init__(self, lookahead: int = 10) → None

LexiRoute constructor.

Parameters:

lookahead – Maximum depth of lookahead employed when picking SWAP for purpose of logical to physical mapping.

class pytket.mapping.MappingManager

Defined by a pytket Architecture object, maps Circuit logical qubits to physically permitted Architecture qubits. Mapping is completed by sequential routing (full or partial) of subcircuits. A custom method for routing (full or partial) of subcircuits can be defined in Python.

__init__(self, architecture: pytket.architecture.Architecture) → None

MappingManager constructor.

Parameters:

architecture – pytket Architecture object.

route_circuit(self, circuit: pytket.circuit.Circuit, routing_methods: collections.abc.Sequence[pytket.mapping.RoutingMethod]) → bool

Maps from given logical circuit to physical circuit. Modification defined by route_subcircuit, but typically this proceeds by insertion of SWAP gates that permute logical qubits on physical qubits.

Parameters:

  • circuit – pytket circuit to be mapped

  • routing_methods – Ranked methods to use for routing subcircuits. In given order, each method is sequentially checked for viability, with the first viable method being used.

class pytket.mapping.MultiGateReorderRoutingMethod

Defines a RoutingMethod object for commuting physically permitted multi-qubit gates to the front of the subcircuit.

__init__(self, max_depth: int = 10, max_size: int = 10) → None

MultiGateReorderRoutingMethod constructor.

Parameters:

  • max_depth – Maximum number of layers of gates checked for simultaneous commutation.

  • max_size – Maximum number of gates checked for simultaneous commutation.

class pytket.mapping.RoutingMethod

Parent class for RoutingMethod, for inheritance purposes only, not for usage.

__init__(self) → None
class pytket.mapping.RoutingMethodCircuit

The RoutingMethod class captures a method for partially mapping logical subcircuits to physical operations as permitted by some architecture. Ranked RoutingMethod objects are used by the MappingManager to route whole circuits.

__init__(self, route_subcircuit: collections.abc.Callable[[pytket.circuit.Circuit, pytket.architecture.Architecture], tuple[bool, pytket.circuit.Circuit, collections.abc.Mapping[pytket.unit_id.UnitID, pytket.unit_id.UnitID], collections.abc.Mapping[pytket.unit_id.UnitID, pytket.unit_id.UnitID]]], max_size: int, max_depth: int) → None

Constructor for a routing method defined by partially routing subcircuits.

Parameters:

  • route_subcircuit – A function declaration that given a Circuit and Architecture object, returns a tuple containing a bool informing MappingManager whether to substitute the returned circuit into the circuit being routed, a new modified circuit, the initial logical to physical qubit mapping of the modified circuit and the permutation of logical to physical qubit mapping given operations in the modified circuit

  • max_size – The maximum number of gates permitted in a subcircuit

  • max_depth – The maximum permitted depth of a subcircuit.