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Format examples/cpp

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Corentin Le Molgat
2018-11-22 13:15:13 +01:00
parent 6b485a7050
commit 24ad8771ef
22 changed files with 856 additions and 912 deletions
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95
examples/cpp/linear_programming.cc
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@@ -18,60 +18,61 @@
#include "ortools/linear_solver/linear_solver.pb.h"
namespace operations_research {
void RunLinearProgrammingExample() {
MPSolver solver("LinearProgrammingExample", MPSolver::GLOP_LINEAR_PROGRAMMING);
const double infinity = solver.infinity();
// x and y are continuous non-negative variables.
MPVariable* const x = solver.MakeNumVar(0.0, infinity, "x");
MPVariable* const y = solver.MakeNumVar(0.0, infinity, "y");
void RunLinearProgrammingExample() {
MPSolver solver("LinearProgrammingExample",
MPSolver::GLOP_LINEAR_PROGRAMMING);
const double infinity = solver.infinity();
// x and y are continuous non-negative variables.
MPVariable* const x = solver.MakeNumVar(0.0, infinity, "x");
MPVariable* const y = solver.MakeNumVar(0.0, infinity, "y");
// Objectif function: Maximize 3x + 4y.
MPObjective* const objective = solver.MutableObjective();
objective->SetCoefficient(x, 3);
objective->SetCoefficient(y, 4);
objective->SetMaximization();
// Objectif function: Maximize 3x + 4y.
MPObjective* const objective = solver.MutableObjective();
objective->SetCoefficient(x, 3);
objective->SetCoefficient(y, 4);
objective->SetMaximization();
// x + 2y <= 14.
MPConstraint* const c0 = solver.MakeRowConstraint(-infinity, 14.0);
c0->SetCoefficient(x, 1);
c0->SetCoefficient(y, 2);
// x + 2y <= 14.
MPConstraint* const c0 = solver.MakeRowConstraint(-infinity, 14.0);
c0->SetCoefficient(x, 1);
c0->SetCoefficient(y, 2);
// 3x - y >= 0.
MPConstraint* const c1 = solver.MakeRowConstraint(0.0, infinity);
c1->SetCoefficient(x, 3);
c1->SetCoefficient(y, -1);
// 3x - y >= 0.
MPConstraint* const c1 = solver.MakeRowConstraint(0.0, infinity);
c1->SetCoefficient(x, 3);
c1->SetCoefficient(y, -1);
// x - y <= 2.
MPConstraint* const c2 = solver.MakeRowConstraint(-infinity, 2.0);
c2->SetCoefficient(x, 1);
c2->SetCoefficient(y, -1);
// x - y <= 2.
MPConstraint* const c2 = solver.MakeRowConstraint(-infinity, 2.0);
c2->SetCoefficient(x, 1);
c2->SetCoefficient(y, -1);
LOG(INFO) << "Number of variables = " << solver.NumVariables();
LOG(INFO) << "Number of constraints = " << solver.NumConstraints();
LOG(INFO) << "Number of variables = " << solver.NumVariables();
LOG(INFO) << "Number of constraints = " << solver.NumConstraints();
const MPSolver::ResultStatus result_status = solver.Solve();
// Check that the problem has an optimal solution.
if (result_status != MPSolver::OPTIMAL) {
LOG(FATAL) << "The problem does not have an optimal solution!";
}
LOG(INFO) << "Solution:";
LOG(INFO) << "x = " << x->solution_value();
LOG(INFO) << "y = " << y->solution_value();
LOG(INFO) << "Optimal objective value = " << objective->Value();
LOG(INFO) << "";
LOG(INFO) << "Advanced usage:";
LOG(INFO) << "Problem solved in " << solver.wall_time() << " milliseconds";
LOG(INFO) << "Problem solved in " << solver.iterations() << " iterations";
LOG(INFO) << "x: reduced cost = " << x->reduced_cost();
LOG(INFO) << "y: reduced cost = " << y->reduced_cost();
const std::vector<double> activities = solver.ComputeConstraintActivities();
LOG(INFO) << "c0: dual value = " << c0->dual_value()
<< " activity = " << activities[c0->index()];
LOG(INFO) << "c1: dual value = " << c1->dual_value()
<< " activity = " << activities[c1->index()];
LOG(INFO) << "c2: dual value = " << c2->dual_value()
<< " activity = " << activities[c2->index()];
const MPSolver::ResultStatus result_status = solver.Solve();
// Check that the problem has an optimal solution.
if (result_status != MPSolver::OPTIMAL) {
LOG(FATAL) << "The problem does not have an optimal solution!";
}
LOG(INFO) << "Solution:";
LOG(INFO) << "x = " << x->solution_value();
LOG(INFO) << "y = " << y->solution_value();
LOG(INFO) << "Optimal objective value = " << objective->Value();
LOG(INFO) << "";
LOG(INFO) << "Advanced usage:";
LOG(INFO) << "Problem solved in " << solver.wall_time() << " milliseconds";
LOG(INFO) << "Problem solved in " << solver.iterations() << " iterations";
LOG(INFO) << "x: reduced cost = " << x->reduced_cost();
LOG(INFO) << "y: reduced cost = " << y->reduced_cost();
const std::vector<double> activities = solver.ComputeConstraintActivities();
LOG(INFO) << "c0: dual value = " << c0->dual_value()
<< " activity = " << activities[c0->index()];
LOG(INFO) << "c1: dual value = " << c1->dual_value()
<< " activity = " << activities[c1->index()];
LOG(INFO) << "c2: dual value = " << c2->dual_value()
<< " activity = " << activities[c2->index()];
}
} // namespace operations_research
int main(int argc, char** argv) {