lp_interface.hpp

Go to the documentation of this file.

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */  /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

#ifndef CMR_LP_INTERFACE_H
#define CMR_LP_INTERFACE_H

#include "lp_util.hpp"

#include <utility>
#include <vector>
#include <memory>

namespace CMR {

namespace Sep {
struct MIRgroup;
}

namespace LP {

class Relaxation {
public:


    Relaxation(); 

    Relaxation(Relaxation &&lp) noexcept; 
    Relaxation& operator=(Relaxation &&lp) noexcept;  

    Relaxation(const Relaxation &lp) = delete;
    Relaxation& operator=(const Relaxation &lp) = delete;

    ~Relaxation(); 



    bool primal_feas() const; 
    bool dual_feas() const; 

    int num_rows() const; 
    int num_cols() const; 

    int it_count() const; 

    double get_coeff(int row, int col) const; 

    void get_rhs(std::vector<double> &rhs, int begin, int end) const;

    std::vector<double> lower_bds(int begin, int end) const;

    std::vector<double> upper_bds(int begin, int end) const;

    std::vector<char> senses(int begin, int end) const;

    void get_col(int col, std::vector<int> &cmatind,
                 std::vector<double> &cmatval) const;

    void get_row(int row, std::vector<int> &rmatind,
                 std::vector<double> &rmatval) const;

    SparseRow get_row(int row) const; 

    void get_row_infeas(const std::vector<double> &x,
                        std::vector<double> &feas_stat, int begin,
                        int end) const;

    void get_col_infeas(const std::vector<double> &x,
                        std::vector<double> &feas_stat, int begin,
                        int end) const;

    double get_objval() const; 

    SolStat get_stat() const; 

    double condition_num() const; 

    void get_x(std::vector<double> &x) const; 

    std::vector<double> lp_vec() const; 


    void get_base(std::vector<int> &colstat, std::vector<int> &rowstat) const;

    Basis basis_obj() const; 

    std::vector<int> col_stat() const; 
    std::vector<int> row_stat() const; 

    void get_row_slacks(std::vector<double> &slack, int begin,
                        int end) const;

    std::vector<double> row_slacks(int begin, int end) const;

    void get_pi(std::vector<double> &pi, int begin, int end) const;

    std::vector<double> pi(int begin, int end) const;

    void get_redcosts(std::vector<double> &redcosts, int begin, int end) const;

    std::vector<double> redcosts(int begin, int end) const;



    void primal_strong_branch(const std::vector<double> &tour_vec,
                              const std::vector<int> &colstat,
                              const std::vector<int> &rowstat,
                              const std::vector<int> &indices,
                              std::vector<Estimate> &down_est,
                              std::vector<Estimate> &up_est,
                              std::vector<Basis> &contra_bases,
                              int itlim, double upperbound);

    void tighten_bound(int index, char sense, double val);

    void change_obj(int index, double val);





    void new_row(char sense, double rhs); 

    void new_rows(const std::vector<char> &sense,
                  const std::vector<double> &rhs); 

    void add_cut(double rhs, char sense,
                 const std::vector<int> &rmatind,
                 const std::vector<double> &rmatval); 

    void add_cut(const SparseRow &sp_row); 

    void add_cuts(const std::vector<double> &rhs,
                  const std::vector<char> &sense,
                  const std::vector<int> &rmatbeg,
                  const std::vector<int> &rmatind,
                  const std::vector<double> &rmatval); 

    void del_set_rows(std::vector<int> &delstat);

    void add_col(const double objval,
                 const std::vector<int> &indices,
                 const std::vector<double> &coeffs,
                 const double lb, const double ub); 

    void del_set_cols(std::vector<int> &delstat);



    void copy_start(const std::vector<double> &x);

    void copy_start(const std::vector<double> &x,
                    const std::vector<int> &col_stat,
                    const std::vector<int> &row_stat);

    void copy_base(const std::vector<int> &col_stat,
                   const std::vector<int> &row_stat);

    void copy_base(const Basis &base);

    void factor_basis(); 



    void switch_steepest(); 

    void primal_opt(); 
    void dual_opt(); 
    void nondegen_pivot(double upper_bound); 

    void cb_nondegen_pivot(double upper_bound, Basis &base, int bas_freq);

    void one_primal_pivot(); 
    void one_dual_pivot(); 

    void primal_recover(); 


    void init_mir_data(Sep::MIRgroup &mir_data); 

private:
    struct solver_impl; 
    std::unique_ptr<solver_impl> simpl_p; 
};

struct NDpivotHandle {
    NDpivotHandle(Relaxation &_rel, double ub, int bfreq)
        : rel(_rel), tour_base(), upper_bound(ub), basis_freq(bfreq) {}

    Relaxation &rel;
    Basis tour_base; 

    double upper_bound; 

    int basis_freq;

    int pfeas_itcount = 0; 
};

}
}

#endif