8bb54b04ef
FYI: find ortools \( -type d -name .git -prune \) -o -type f -print0 | xargs -0 sed -i 's/\(Copyright 2010\)-2018/\1-2021/g'
77 lines
2.8 KiB
C++
77 lines
2.8 KiB
C++
// Copyright 2010-2021 Google LLC
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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#ifndef OR_TOOLS_BOP_INTEGRAL_SOLVER_H_
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#define OR_TOOLS_BOP_INTEGRAL_SOLVER_H_
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#include "ortools/bop/bop_parameters.pb.h"
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#include "ortools/bop/bop_types.h"
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#include "ortools/lp_data/lp_data.h"
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#include "ortools/util/time_limit.h"
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namespace operations_research {
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namespace bop {
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// This class implements an Integer Programming solver, i.e. the solver solves
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// problems with both integral and boolean variables, linear constraint and
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// linear objective function.
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class IntegralSolver {
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public:
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IntegralSolver();
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~IntegralSolver() {}
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// Sets the solver parameters.
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// See the proto for an extensive documentation.
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void SetParameters(const BopParameters& parameters) {
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parameters_ = parameters;
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}
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BopParameters parameters() const { return parameters_; }
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// Solves the given linear program and returns the solve status.
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ABSL_MUST_USE_RESULT BopSolveStatus
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Solve(const glop::LinearProgram& linear_problem);
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ABSL_MUST_USE_RESULT BopSolveStatus SolveWithTimeLimit(
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const glop::LinearProgram& linear_problem, TimeLimit* time_limit);
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// Same as Solve() but starts from the given solution.
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// TODO(user): Change the API to accept a partial solution instead since the
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// underlying solver supports it.
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ABSL_MUST_USE_RESULT BopSolveStatus
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Solve(const glop::LinearProgram& linear_problem,
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const glop::DenseRow& user_provided_initial_solution);
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ABSL_MUST_USE_RESULT BopSolveStatus
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SolveWithTimeLimit(const glop::LinearProgram& linear_problem,
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const glop::DenseRow& user_provided_initial_solution,
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TimeLimit* time_limit);
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// Returns the objective value of the solution with its offset.
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glop::Fractional objective_value() const { return objective_value_; }
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// Returns the best bound found so far.
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glop::Fractional best_bound() const { return best_bound_; }
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// Returns the solution values. Note that the values only make sense when a
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// solution is found.
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const glop::DenseRow& variable_values() const { return variable_values_; }
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private:
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BopParameters parameters_;
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glop::DenseRow variable_values_;
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glop::Fractional objective_value_;
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glop::Fractional best_bound_;
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DISALLOW_COPY_AND_ASSIGN(IntegralSolver);
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};
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} // namespace bop
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} // namespace operations_research
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#endif // OR_TOOLS_BOP_INTEGRAL_SOLVER_H_
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