Sampler

Sampler(backend=None, session=None, options=None)

Class for interacting with Qiskit Runtime Sampler primitive service.

Qiskit Runtime Sampler primitive service calculates quasi-probability distribution of bitstrings from quantum circuits.

The run() method can be used to submit circuits and parameters to the Sampler primitive.

You are encouraged to use Session to open a session, during which you can invoke one or more primitives. Jobs submitted within a session are prioritized by the scheduler, and data is cached for efficiency.

Example:

from qiskit.test.reference_circuits import ReferenceCircuits
from qiskit_ibm_runtime import QiskitRuntimeService, Session, Sampler
 
service = QiskitRuntimeService(channel="ibm_cloud")
bell = ReferenceCircuits.bell()
 
with Session(service, backend="ibmq_qasm_simulator") as session:
    sampler = Sampler(session=session)
 
    job = sampler.run(bell, shots=1024)
    print(f"Job ID: {job.job_id()}")
    print(f"Job result: {job.result()}")
 
    # You can run more jobs inside the session

Initializes the Sampler primitive.

Parameters

• backend (Union[str, IBMBackend, None]) – Backend to run the primitive. This can be a backend name or an IBMBackend instance. If a name is specified, the default account (e.g. QiskitRuntimeService()) is used.

• session (Union[Session, str, IBMBackend, None]) –

  Session in which to call the primitive.

  If both session and backend are specified, session takes precedence. If neither is specified, and the primitive is created inside a qiskit_ibm_runtime.Session context manager, then the session is used. Otherwise if IBM Cloud channel is used, a default backend is selected.

• options (Union[Dict, Options, None]) – Primitive options, see Options for detailed description. The backend keyword is still supported but is deprecated.

Attributes

circuits

Quantum circuits to be sampled.

Return type

tuple[QuantumCircuit, ...]

Returns

The quantum circuits to be sampled.

options

Return options values for the sampler.

Return type

Options

Returns

options

parameters

Parameters of quantum circuits.

Return type

tuple[ParameterView, ...]

Returns

List of the parameters in each quantum circuit.

session

Return session used by this primitive.

Return type

Optional[Session]

Returns

Session used by this primitive, or None if session is not used.

Methods

run

run(circuits, parameter_values=None, **kwargs)

Submit a request to the sampler primitive.

Parameters

• circuits (QuantumCircuit | Sequence[QuantumCircuit]) – A (parameterized) QuantumCircuit or a list of (parameterized) QuantumCircuit.
• parameter_values (Sequence[float] | Sequence[Sequence[float]] | None) – Concrete parameters to be bound.
• **kwargs – Individual options to overwrite the default primitive options. These include the runtime options in qiskit_ibm_runtime.RuntimeOptions.

Return type

RuntimeJob

Returns

Submitted job. The result of the job is an instance of qiskit.primitives.SamplerResult.

Raises

ValueError – Invalid arguments are given.

set_options

set_options(**fields)

Set options values for the sampler.

Parameters

**fields – The fields to update the options

Return type

None