OperationsResearch Namespace Reference

Classes
class	AcceptanceStrategy
	Determines when a neighbor solution, obtained by the application of a perturbation and improvement step to a reference solution, is used to replace the reference solution. More...
class	IteratedLocalSearchParameters
	Specifies the behavior of a search based on ILS. More...
class	LinearSolverReflection
	Holder for reflection information generated from ortools/linear_solver/linear_solver.proto. More...
class	MPAbsConstraint
	Sets a variable's value to the absolute value of another variable. More...
class	MPArrayConstraint
	Sets a variable's value equal to a function on a set of variables. More...
class	MPArrayWithConstantConstraint
	Sets a variable's value equal to a function on a set of variables and, optionally, a constant. More...
class	MPConstraintProto
	A linear constraint is always of the form: lower_bound <= sum of linear term elements <= upper_bound, where lower_bound and upper_bound: More...
class	MPGeneralConstraintProto
	General constraints. See each individual proto type for more information. More...
class	MPIndicatorConstraint
	Indicator constraints encode the activation or deactivation of linear constraints given the value of one Boolean variable in the model. For example: y = 0 => 2 * x1 + 3 * x2 >= 42 The 2 * x1 + 3 * x2 >= 42 constraint is only active if the variable y is equal to 0. As of 2019/04, only SCIP, CP-SAT and Gurobi support this constraint type. More...
class	MPModelDeltaProto
	Encodes a full MPModelProto by way of referencing to a "baseline" MPModelProto stored in a file, and a "delta" to apply to this model. More...
class	MPModelProto
	MPModelProto contains all the information for a Linear Programming model. More...
class	MPModelRequest
	Next id: 18. More...
class	MPQuadraticConstraint
	Quadratic constraints of the form lb <= sum a_i x_i + sum b_ij x_i x_j <= ub, where a, b, lb and ub are constants, and x are the model's variables. Quadratic matrices that are Positive Semi-Definite, Second-Order Cones or rotated Second-Order Cones are always accepted. Other forms may or may not be accepted depending on the underlying solver used. See https://scip.zib.de/doc/html/cons__quadratic_8h.php and https://www.gurobi.com/documentation/9.0/refman/constraints.html#subsubsection:QuadraticConstraints. More...
class	MPQuadraticObjective
	Quadratic part of a model's objective. Added with other objectives (such as linear), this creates the model's objective function to be optimized. More...
class	MPSolution
class	MPSolutionResponse
	Next id: 12. More...
class	MPSolveInfo
class	MPSolverCommonParameters
	MPSolverCommonParameters holds advanced usage parameters that apply to any of the solvers we support. All of the fields in this proto can have a value of unspecified. In this case each inner solver will use their own safe defaults. Some values won't be supported by some solvers. The behavior in that case is not defined yet. More...
class	MPSosConstraint
	Special Ordered Set (SOS) constraints of type 1 or 2. See https://en.wikipedia.org/wiki/Special_ordered_set As of 2019/04, only SCIP and Gurobi support this constraint type. More...
class	MPVariableProto
	A variable is always constrained in the form: lower_bound <= x <= upper_bound where lower_bound and upper_bound: More...
class	OptionalDouble
	To support 'unspecified' double value in proto3, the simplest is to wrap any double value in a nested message (has_XXX works for message fields). More...
class	PartialVariableAssignment
	This message encodes a partial (or full) assignment of the variables of a MPModelProto problem. The indices in var_index should be unique and valid variable indices of the associated problem. More...
class	PerturbationStrategy
	Defines how a reference solution is perturbed. More...
class	RoutingIlsReflection
	Holder for reflection information generated from ortools/constraint_solver/routing_ils.proto. More...
class	RuinRecreateParameters
	Parameters to configure a perturbation based on a ruin and recreate approach. More...
class	RuinStrategy
	Ruin strategies, used in perturbation based on ruin and recreate approaches. More...
class	SetCoverProto
class	SetCoverReflection
	Holder for reflection information generated from ortools/algorithms/set_cover.proto. More...
class	SetCoverSolutionResponse

Enumerations
enum	MPSolverResponseStatus {   MpsolverOptimal = 0 , MpsolverFeasible = 1 , MpsolverInfeasible = 2 , MpsolverUnbounded = 3 ,   MpsolverAbnormal = 4 , MpsolverNotSolved = 6 , MpsolverModelIsValid = 97 , MpsolverCancelledByUser = 98 ,   MpsolverUnknownStatus = 99 , MpsolverModelInvalid = 5 , MpsolverModelInvalidSolutionHint = 84 , MpsolverModelInvalidSolverParameters = 85 ,   MpsolverSolverTypeUnavailable = 7 , MpsolverIncompatibleOptions = 113 }
	Status returned by the solver. They follow a hierarchical nomenclature, to allow us to add more enum values in the future. Clients should use InCategory() to match these enums, with the following C++ pseudo-code: More...

Enumeration Type Documentation

MPSolverResponseStatus

enum OperationsResearch.MPSolverResponseStatus

Status returned by the solver. They follow a hierarchical nomenclature, to allow us to add more enum values in the future. Clients should use InCategory() to match these enums, with the following C++ pseudo-code:

bool InCategory(MPSolverResponseStatus status, MPSolverResponseStatus cat) { if (cat == MPSOLVER_OPTIMAL) return status == MPSOLVER_OPTIMAL; while (status > cat) status >>= 4; return status == cat; }

Enumerator
MpsolverOptimal	The solver found the proven optimal solution. This is what should be returned in most cases. Warning for historical reason, the value is zero, which means that this value can't have any subcategories.
MpsolverFeasible	The solver had enough time to find some solution that satisfies all constraints, but it did not prove optimality (which means it may or may not have reached the optimal). This can happen for large LP models (Linear Programming), and is a frequent response for time-limited MIPs (Mixed Integer Programming). In the MIP case, the difference between the solution 'objective_value' and 'best_objective_bound' fields of the MPSolutionResponse will give an indication of how far this solution is from the optimal one.
MpsolverInfeasible	The model does not have any solution, according to the solver (which "proved" it, with the caveat that numerical proofs aren't actual proofs), or based on trivial considerations (eg. a variable whose lower bound is strictly greater than its upper bound).
MpsolverUnbounded	There exist solutions that make the magnitude of the objective value as large as wanted (i.e. -infinity (resp. +infinity) for a minimization (resp. maximization) problem.
MpsolverAbnormal	An error (most probably numerical) occurred. One likely cause for such errors is a large numerical range among variable coefficients (eg. 1e-16, 1e20), in which case one should try to shrink it.
MpsolverNotSolved	The solver did not have a chance to diagnose the model in one of the categories above.
MpsolverModelIsValid	Like "NOT_SOLVED", but typically used by model validation functions returning a "model status", to enhance readability of the client code.
MpsolverCancelledByUser	The solve was interrupted by the user, and the solver didn't have time to return a proper status.
MpsolverUnknownStatus	Special value: the solver status could not be properly translated and is unknown.
MpsolverModelInvalid	Model errors. These are always deterministic and repeatable. They should be accompanied with a string description of the error.
MpsolverModelInvalidSolutionHint	Something is wrong with the fields "solution_hint_var_index" and/or "solution_hint_var_value".
MpsolverModelInvalidSolverParameters	Something is wrong with the solver_specific_parameters request field.
MpsolverSolverTypeUnavailable	Implementation error: the requested solver implementation is not available (see MPModelRequest.solver_type). The linear solver binary was probably not linked with the required library, eg ///<ortools/linear_solver:linear_solver_scip for SCIP.
MpsolverIncompatibleOptions	Some of the selected options were incompatible, e.g. a cancellable solve was requested via SolverClient::SolveMipRemotely() with an underlying solver that doesn't support cancellation. status_str should contain a description of the issue.

Definition at line 197 of file LinearSolver.pb.cs.