C++ Hello World - Segmentation Fault

[hlefebvr]

Hello,

I am trying to build a minimal example for using MibS with C++.

Context

I am trying to model the following problem using the C++ API:

 min  -x − 7y
 s.t.   -3x + 2y ≤ 12
             x + 2y ≤ 20
             x ≤ 10
             y ∈ arg min {z : 2x - z ≤ 7,
                              -2x + 4z ≤ 16,
                              z ≤ 5}

Setting

• MibS 1.2 as built using coinbrew and linked with Cplex - though the problem I am facing seems indifferent to CPLEX.
• Ubuntu 22.04 LTS
• CMake as build system
• C++17

My Attempt

So far, I have tried with the following code.

    std::unique_ptr<OsiSolverInterface> solver(new OsiCpxSolverInterface());

    MibSModel model;
    model.setSolver(solver.get());

   // AUXILIARY DATA
    std::vector<int> upper_level_variables_indices = { 0,  };
    std::vector<int> lower_level_variables_indices = { 1,  };
    std::vector<int> upper_level_constraints_indices = { 0, 1,  };
    std::vector<int> lower_level_constraints_indices = { 2, 3,  };
    std::vector<double> lower_level_objective_coefficients = { 1,  };

    model.loadAuxiliaryData(
            (int) lower_level_variables_indices.size(),
            (int) lower_level_constraints_indices.size(),
            lower_level_variables_indices.data(),
            lower_level_constraints_indices.data(),
            1.,
            lower_level_objective_coefficients.data(),
            (int) upper_level_variables_indices.size(),
            (int) upper_level_constraints_indices.size(),
            upper_level_variables_indices.data(),
            upper_level_constraints_indices.data(),
            0,
            nullptr,
            0,
            nullptr,
            nullptr,
            nullptr
    );

   // PROBLEM DATA

    std::vector<double> variable_lower_bounds = { 0, 0,  };
    std::vector<double> variable_upper_bounds = { 10, 5,  };
    std::vector<char> variable_types = { 'I', 'I',  };
    std::vector<double> constraint_lower_bounds = { -1e+20, -1e+20, -1e+20, -1e+20,  };
    std::vector<double> constraint_upper_bounds = { 12, 20, 7, 16,  };
    std::vector<char> constraint_types = { 'L', 'L', 'L', 'L',  };
    std::vector<double> objective = { -1, -7,  };

    CoinPackedMatrix matrix(false, 0, 2);

    CoinPackedVector row1;
    row1.insert(0, -3);
    row1.insert(1, 2);
    matrix.appendRow(row1);

    CoinPackedVector row2;
    row2.insert(0, 1);
    row2.insert(1, 2);
    matrix.appendRow(row2);

    CoinPackedVector row3;
    row3.insert(0, 2);
    row3.insert(1, -1);
    matrix.appendRow(row3);

    CoinPackedVector row4;
    row4.insert(0, -2);
    row4.insert(1, 4);
    matrix.appendRow(row4);

    model.loadProblemData(
            matrix,
            variable_lower_bounds.data(),
            variable_upper_bounds.data(),
            objective.data(),
            constraint_lower_bounds.data(),
            constraint_upper_bounds.data(),
            variable_types.data(),
            1.,
            1e+20,
            constraint_types.data()
    );

Quesitons and Problems

• I get a Segmentation Fault when running this code. This happens in the call of loadProblemData and, in particular, seems to be in setUpperRowData.
• What does the arguments structRowXX relate to ?

Thank you,

Henri.