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SCIP

SCIP is a freely available solver for mixed integer programming (MIP) and mixed integer nonlinear programming (MINLP) developed by the Zuse Institut Berlin. Currently it is amongst the fastest non-commercial solvers available.

Note

SCIP may introduce auxiliary variables during the solving process, e.g., the variable quadobjvar (see https://scipopt.org/doc/html/reader__lp_8c_source.php in line 1336). These variables will be stored in the solution metadata under the key auxiliary_variables.

Compatible Backends

The SCIP algorithm supports the following backends:

By default, SCIP uses the ZIB backend.

Initialization

The following section outlines the default configurations of SCIP. You can also specify other compatible backends for the algorithm. When backend=None is specified, the default backend will be initialized automatically. In this case, if the backend requires a token, it will be taken from the environment variables.

Default Configuration
from luna_quantum.solve.parameters.algorithms import SCIP

algorithm = SCIP(
    backend=None
)

Parameter Details

For a complete overview of available parameters and their usage, see the SCIP API Reference.

Usage

from luna_quantum import LunaSolve

LunaSolve.authenticate("<YOUR_LUNA_API_KEY>")

# Define your model and algorithm
model = ...
algorithm = ...

solve_job = algorithm.run(model, name="my-solve-job")

API Reference

Bases: LunaAlgorithm[ZIB]

Parameters for the "Solve Constraint Integer Programming" (SCIP) solver.

backend class-attribute instance-attribute 

backend: BACKEND_TYPE | None = Field(default=None, exclude=True, repr=False)

model_config class-attribute instance-attribute 

model_config = ConfigDict(
    arbitrary_types_allowed=True, extra="allow", validate_assignment=True
)

get_compatible_backends classmethod 

get_compatible_backends() -> tuple[type[ZIB], ...]

Check at runtime if the used backend is compatible with the solver.

Returns:

Type Description
tuple[type[IBackend], ...]

True if the backend is compatible with the solver, False otherwise.

get_default_backend classmethod 

get_default_backend() -> ZIB

Return the default backend implementation.

This property must be implemented by subclasses to provide the default backend instance to use when no specific backend is specified.

Returns:

Type Description
BACKEND_TYPE

An instance of a class implementing the IBackend interface that serves as the default backend.

run 

run(
    model: Model | str,
    name: str | None = None,
    backend: BACKEND_TYPE | None = None,
    client: LunaSolve | str | None = None,
    *args: Any,
    **kwargs: Any,
) -> SolveJob

Run the configured solver.

Parameters:

Name Type Description Default
model Model or str

The model to be optimized or solved. It could be an Model instance or a string identifier representing the model id.

 required
name str | None

If provided, the name of the job. Defaults to None.

 None
backend BACKEND_TYPE | None

Backend to use for the solver. If not provided, the default backend is used.

 None
client LunaSolve or str

The client interface used to interact with the backend services. If not provided, a default client will be used.

 None
*args Any

Additional arguments that will be passed to the solver or client.

 ()
**kwargs Any

Additional keyword parameters for configuration or customization.

 {}

Returns:

Type Description
SolveJob

The job object containing the information about the solve process.