model_validator.h

// Copyright 2010-2018 Google LLC
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#ifndef OR_TOOLS_LINEAR_SOLVER_MODEL_VALIDATOR_H_
#define OR_TOOLS_LINEAR_SOLVER_MODEL_VALIDATOR_H_

#include <string>

#include "ortools/linear_solver/linear_solver.pb.h"

namespace operations_research {
// Returns an empty std::string iff the model is valid and not trivially
// infeasible. Otherwise, returns a description of the first error or trivial
// infeasibility encountered.
//
// NOTE(user): the code of this method (and the client code too!) is
// considerably simplified by this std::string-based, simple API. If clients
// require it, we could add a formal error status enum.
std::string FindErrorInMPModelProto(const MPModelProto& model);

// Returns an empty std::string if the solution hint given in the model is a
// feasible solution. Otherwise, returns a description of the first reason for
// infeasibility.
//
// This function can be useful for debugging/checking that the given solution
// hint is feasible when it is expected to be the case. The feasibility is
// checked up to the given tolerance using the
// ::operations_research::IsLowerWithinTolerance() function.
std::string FindFeasibilityErrorInSolutionHint(const MPModelProto& model,
                                               double tolerance);

}  // namespace operations_research

#endif  // OR_TOOLS_LINEAR_SOLVER_MODEL_VALIDATOR_H_