JIJ SQOA Solver API reference

Type: str or dict[str, float]

The optimization problem in one of the following formats. For more information, see Accepted problem formats.

• A serialized OMMX instance. Serialize an ommx.v1.Instance with to_bytes() and encode the bytes as standard padded Base64 (RFC 4648).
  • URL-safe Base64, missing padding, and embedded whitespace are rejected.
  • The instance must already be in QUBO form.
  • Example: base64.b64encode(instance.to_bytes()).decode(), which for a two-variable QUBO gives:

  EiYQARoJEQAAAAAAAPA/IgF4KgEAMhEKCnN1YnNjcmlwdHMSA1swXRIoCAEQARoJEQAAAAAAAPA/IgF4KgEBMhEKCnN1YnNjcmlwdHMSA1sxXRosGioKAQASAQEaCAAAAAAAAADAIhgKCwgBEQAAAAAAAPA/CgkRAAAAAAAA8D8oAjoA
• A coefficient dictionary whose keys are stringified tuples of variable IDs, and whose values are the coefficients:
  • "()" for the constant
  • "(i,)" for a linear term
  • "(i, j)" for a quadratic term
  • Example: {"()": 2.5, "(7,)": -1, "(11,)": 2, "(7, 11)": 3}
• Required: Yes

Type: str

The domain of the decision variables: "binary" for variables in {0, 1} or "spin" for variables in {-1, +1}.

• An OMMX instance must be submitted with "binary".
• "spin" is accepted only for coefficient dictionaries.
• The result reports the variable values in the same domain.
• Required: Yes
• Example: "binary"

Type: str or None

Default value: None

Name of the IBM Quantum® backend that runs the sampling jobs. When supplied, the value must be a non-empty string without leading or trailing whitespace, and it must name a backend that is accessible to the instance used to run the function.

• A name that cannot be resolved raises an error. The function does not fall back to automatic selection.
• When omitted or None, the function selects the least busy operational QPU that is accessible to that instance, equivalent to QiskitRuntimeService.least_busy(operational=True, simulator=False), and records the selected backend in the job logs.
• Required: No
• Example: "ibm_fez"

Type: dict[str, Any]

Options that control the sampling budget, reproducibility, session usage, classical post-processing, and job tags. Specify options as a dictionary. The function rejects unknown keys. See the following list of available options and their default values.

• Required: No

Example:

{
    "shots": 4096,
    "seed": 42,
    "session": True,
    "postprocessing_level": 1,
    "job_tags": ["mis"]
}

Available options:

shots

seed

session

postprocessing_level

job_tags

Type: `dict[str, Any]`

Solution and metadata. job.result() returns a dictionary with exactly four keys, solution, objective_value, feasible, and metadata, described under Result dictionary.

Example:

{
    'solution': {'x_0': 1.0, 'x_1': 0.0},
    'objective_value': 1.0,
    'feasible': True,
    'metadata': {
        'solver_info': {
            'seed': 42,
            'solution_before_postprocessing': {'x_0': 0.0, 'x_1': 0.0},
            'ommx_solution': 'Cg8KCREAAAAAAADwPwoCCAER...'
        },
        'resource_usage': {
            'RUNNING: MAPPING': {'CPU_TIME': 0.9},
            'RUNNING: OPTIMIZING_FOR_HARDWARE': {'CPU_TIME': 2.1},
            'RUNNING: WAITING_FOR_QPU': {'CPU_TIME': 41.7},
            'RUNNING: EXECUTING_QPU': {'QPU_TIME': 4.8},
            'RUNNING: POST_PROCESSING': {'CPU_TIME': 1.3}
        }
    }
}

Type: `dict[str, float]`

The single best assignment found after all post-processing, keyed by variable. If several candidates share the best objective value, one of them is returned.

Each key is name_ID: the variable name followed by an underscore and the decimal decision variable ID, for example x_17. Keys are listed in ascending ID order, which keeps them unique even when names repeat.

• For an OMMX instance, the name and ID come from the instance. A variable without a name uses x, and subscripts are not part of the key.
• For a dictionary problem, the keys are x_ID with the IDs used in the submitted dictionary.

The assignment is complete. For an OMMX instance, it includes variables fixed by pre-processing, dependent and slack variables reconstructed from the OMMX conversion metadata, and variables that the objective does not use.

Values are 0 or 1 for "binary" and -1 or +1 for "spin".

Type: `float`

Objective value of the returned assignment, evaluated on the submitted problem rather than on the internal quantum relaxation.

• For an OMMX instance, it is the objective of the instance in the sense of the instance.
• For a dictionary problem, it is the value of the coefficient dictionary in the original variable domain, including the constant term.

Type: `bool`

Whether the assignment satisfies the constraints recorded in the submitted instance, including constraints that were removed by the OMMX QUBO conversion, as evaluated by the OMMX SDK. A dictionary problem is unconstrained, so its feasibility refers only to the variable domain.

Type: `dict[str, Any]`

Contains exactly two keys, solver_info and resource_usage.

solver_info

resource_usage