Solver#

A solver is a resource for solving problems.

Solvers are responsible for:

Encoding submitted problems
Checking submitted parameters
Decoding answers
Adding problems to a client’s submission queue

You can list all solvers available to a Client with its get_solvers() method and select and return one with its get_solver() method.

Class#

Solver[source]#: alias of StructuredSolver

class BaseSolver(client: dwave.cloud.Client | None, data: dict | SolverConfiguration)[source]#

Base class for a general D-Wave solver.

This class provides Ising, QUBO and BQM sampling methods and encapsulates the solver description returned from the D-Wave cloud API.

Parameters:

client (Client) – Client that manages access to this solver.
data (dict) – Data from the server describing this solver.

Examples

This example creates a client using the local system’s default D-Wave Cloud Client configuration file and checks the identity of its default solver.

>>> from dwave.cloud import Client
>>> with Client.from_config() as client:
...     solver = client.get_solver()
...     solver.name     
'Advantage_system4'

class StructuredSolver(*args, **kwargs)[source]#

Class for D-Wave structured solvers.

This class provides Ising, QUBO and BQM sampling methods and encapsulates the solver description returned from the D-Wave cloud API.

Parameters:

client (Client) – Client that manages access to this solver.
data (dict) – Data from the server describing this solver.

UnstructuredSolver[source]#: alias of BQMSolver

Methods#

`StructuredSolver.check_problem`(linear, quadratic)	Test if an Ising model matches the graph provided by the solver.
`StructuredSolver.estimate_qpu_access_time`(...)	Estimates QPU access time for a submission to the selected solver.
`StructuredSolver.max_num_reads`(**params)	Returns the maximum number of reads for the given solver parameters.
`StructuredSolver.reformat_parameters`(...[, ...])	Reformat some solver parameters for SAPI.
`StructuredSolver.sample_bqm`(bqm[, label])	Sample from the specified BQM.
`StructuredSolver.sample_ising`(linear, quadratic)	Sample from the specified Ising model.
`StructuredSolver.sample_qubo`(qubo[, offset, ...])	Sample from the specified QUBO.
`UnstructuredSolver.sample_ising`(linear, ...)	Sample from the specified Ising model.
`UnstructuredSolver.sample_qubo`(qubo[, ...])	Sample from the specified QUBO.
`UnstructuredSolver.sample_bqm`(bqm[, label])	Sample from the specified BQM.
`UnstructuredSolver.upload_bqm`(bqm)	Upload the specified BQM to SAPI, returning a Problem ID that can be used to submit the BQM to this solver (i.e. call the `sample_bqm()` method).
`BQMSolver.sample_ising`(linear, quadratic[, ...])	Sample from the specified Ising model.
`BQMSolver.sample_qubo`(qubo[, offset, label])	Sample from the specified QUBO.
`BQMSolver.sample_bqm`(bqm[, label])	Sample from the specified BQM.
`BQMSolver.upload_bqm`(bqm)	Upload the specified BQM to SAPI, returning a Problem ID that can be used to submit the BQM to this solver (i.e. call the `sample_bqm()` method).
`CQMSolver.sample_cqm`(cqm[, label])	Sample from the specified CQM.
`CQMSolver.upload_cqm`(cqm)	Upload the specified CQM to SAPI, returning a Problem ID that can be used to submit the CQM to this solver (i.e. call the .sample_cqm method).
`DQMSolver.sample_dqm`(dqm[, label])	Sample from the specified DQM.
`DQMSolver.upload_dqm`(dqm)	Upload the specified DQM to SAPI, returning a Problem ID that can be used to submit the DQM to this solver (i.e. call the .sample_dqm method).
`NLSolver.sample_nlm`(model[, label, ...])	Sample from the specified NL model.
`NLSolver.upload_nlm`(model, **upload_params)	Upload the specified NL model to SAPI, returning a Problem ID that can be used to submit the NL model to this solver (i.e. call the `sample_nlm()` method).

Properties#

`BaseSolver.identity`	Solver identity/specification (name, version, etc)
`BaseSolver.name`	Solver name.
`BaseSolver.avg_load`	Solver's average load, at the time of description fetch.
`BaseSolver.online`	Is this solver online (or offline)?
`BaseSolver.qpu`	Is this a QPU-based solver?
`BaseSolver.hybrid`	Is this a hybrid quantum-classical solver?
`BaseSolver.software`	Is this a software-based solver?
`StructuredSolver.nodes`	The nodes in this solver's graph.
`StructuredSolver.variables`	Alias for `nodes`.
`StructuredSolver.edges`	(a,b) and (b,a).
`StructuredSolver.couplers`	Alias for `edges`.
`StructuredSolver.undirected_edges`	The edges in this solver's graph, with each edge represented only once.
`StructuredSolver.graph_id`	QPU solver working graph id.
`StructuredSolver.version`	QPU solver version dict (contains at least `graph_id`).
`StructuredSolver.num_active_qubits`	The number of active (encoding) qubits.
`StructuredSolver.num_qubits`	Nominal number of qubits on chip (includes active AND inactive).
`StructuredSolver.is_vfyc`	Is this a virtual full-yield chip?
`StructuredSolver.has_flux_biases`	Solver supports/accepts `flux_biases`.
`StructuredSolver.has_anneal_schedule`	Solver supports/accepts `anneal_schedule`.
`StructuredSolver.lower_noise`