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FakeCambridgeV2

class FakeCambridgeV2

GitHub

Bases: FakeBackendV2

A fake Cambridge backend.

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FakeBackendV2 initializer.


Attributes

backend_name

Default value: 'fake_cambridge'

conf_filename

Default value: 'conf_cambridge.json'

coupling_map

Return the CouplingMap object

defs_filename

Default value: None

dirname

Default value: '/home/runner/work/qiskit-ibm-runtime/qiskit-ibm-runtime/qiskit_ibm_runtime/fake_provider/backends/cambridge'

dt

Return the system time resolution of input signals

This is required to be implemented if the backend supports Pulse scheduling.

Returns

The input signal timestep in seconds. If the backend doesn’t define dt, None will be returned.

dtm

Return the system time resolution of output signals

Returns

The output signal timestep in seconds.

instruction_durations

Return the InstructionDurations object.

instruction_schedule_map

Return the InstructionScheduleMap for the instructions defined in this backend’s target.

instructions

A list of Instruction tuples on the backend of the form (instruction, (qubits)

max_circuits

meas_map

Return the grouping of measurements which are multiplexed This is required to be implemented if the backend supports Pulse scheduling.

Returns

The grouping of measurements which are multiplexed

num_qubits

Return the number of qubits the backend has.

operation_names

A list of instruction names that the backend supports.

operations

A list of Instruction instances that the backend supports.

options

Return the options for the backend

The options of a backend are the dynamic parameters defining how the backend is used. These are used to control the run() method.

props_filename

Default value: 'props_cambridge.json'

provider

Return the backend Provider.

Returns

the Provider responsible for the backend.

Return type

Provider

target

A qiskit.transpiler.Target object for the backend.

Return type

Target

version

Default value: 2

name

Name of the backend.

description

Optional human-readable description.

online_date

Date that the backend came online.

backend_version

Version of the backend being provided. This is not the same as BackendV2.version, which is the version of the Backend abstract interface.


Methods

acquire_channel

acquire_channel(qubit)

GitHub

Return the acquisition channel for the given qubit.

This is required to be implemented if the backend supports Pulse scheduling.

Returns

The Qubit measurement acquisition line.

Return type

AcquireChannel

Parameters

qubit (int)

check_faulty

check_faulty(circuit)

GitHub

Check if the input circuit uses faulty qubits or edges.

Parameters

circuit (QuantumCircuit) – Circuit to check.

Raises

ValueError – If an instruction operating on a faulty qubit or edge is found.

Return type

None

configuration

configuration()

GitHub

Return the backend configuration.

Return type

QasmBackendConfiguration | PulseBackendConfiguration

control_channel

control_channel(qubits)

GitHub

Return the secondary drive channel for the given qubit

This is typically utilized for controlling multiqubit interactions. This channel is derived from other channels.

This is required to be implemented if the backend supports Pulse scheduling.

Parameters

qubits (Iterable[int]) – Tuple or list of qubits of the form (control_qubit, target_qubit).

Returns

The multi qubit control line.

Return type

List[ControlChannel]

defaults

defaults(refresh=False)

GitHub

Return the pulse defaults for the backend

Parameters

  • refresh (bool) – If True, re-retrieve the backend defaults from the
  • file. (local)

Returns

The backend pulse defaults or None if the backend does not support pulse.

Return type

PulseDefaults

drive_channel

drive_channel(qubit)

GitHub

Return the drive channel for the given qubit.

This is required to be implemented if the backend supports Pulse scheduling.

Returns

The Qubit drive channel

Return type

DriveChannel

Parameters

qubit (int)

measure_channel

measure_channel(qubit)

GitHub

Return the measure stimulus channel for the given qubit.

This is required to be implemented if the backend supports Pulse scheduling.

Returns

The Qubit measurement stimulus line

Return type

MeasureChannel

Parameters

qubit (int)

properties

properties(refresh=False)

GitHub

Return the backend properties

Parameters

  • refresh (bool) – If True, re-retrieve the backend properties
  • file. (from the local)

Returns

The backend properties.

Return type

BackendProperties

qubit_properties

qubit_properties(qubit)

Return QubitProperties for a given qubit.

If there are no defined or the backend doesn’t support querying these details this method does not need to be implemented.

Parameters

qubit (int | List[int]) – The qubit to get the QubitProperties object for. This can be a single integer for 1 qubit or a list of qubits and a list of QubitProperties objects will be returned in the same order

Returns

The QubitProperties object for the specified qubit. If a list of qubits is provided a list will be returned. If properties are missing for a qubit this can be None.

Raises

NotImplementedError – if the backend doesn’t support querying the qubit properties

Return type

QubitProperties | List[QubitProperties]

refresh

refresh(service)

GitHub

Update the data files from its real counterpart

This method pulls the latest backend data files from their real counterpart and overwrites the corresponding files in the local installation: * ../fake_provider/backends/{backend_name}/conf_{backend_name}.json * ../fake_provider/backends/{backend_name}/defs_{backend_name}.json * ../fake_provider/backends/{backend_name}/props_{backend_name}.json

The new data files will persist through sessions so the files will stay updated unless they

are manually reverted locally or when qiskit-ibm-runtime is upgraded/reinstalled.

Parameters

service (QiskitRuntimeService) – A QiskitRuntimeService instance

Raises

  • ValueError – if the provided service is a non-QiskitRuntimeService instance.
  • Exception – If the real target doesn’t exist or can’t be accessed

Return type

None

run

run(run_input, **options)

GitHub

Run on the fake backend using a simulator.

This method runs circuit jobs (an individual or a list of QuantumCircuit ) and pulse jobs (an individual or a list of Schedule or ScheduleBlock) using BasicSimulator or Aer simulator and returns a Job object.

If qiskit-aer is installed, jobs will be run using AerSimulator with noise model of the fake backend. Otherwise, jobs will be run using BasicSimulator without noise.

Currently noisy simulation of a pulse job is not supported yet in FakeBackendV2.

Parameters

  • run_input (QuantumCircuit or Schedule or ScheduleBlock or list) – An individual or a list of QuantumCircuit, ScheduleBlock, or Schedule objects to run on the backend.
  • options – Any kwarg options to pass to the backend for running the config. If a key is also present in the options attribute/object then the expectation is that the value specified will be used instead of what’s set in the options object.

Returns

The job object for the run

Return type

Job

Raises

QiskitError – If a pulse job is supplied and qiskit-aer is not installed.

set_options

set_options(**fields)

Set the options fields for the backend

This method is used to update the options of a backend. If you need to change any of the options prior to running just pass in the kwarg with the new value for the options.

Parameters

fields – The fields to update the options

Raises

AttributeError – If the field passed in is not part of the options

status

status()

GitHub

Return the backend status.

Returns

The status of the backend.

Return type

BackendStatus

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