/******************************************************** Xpress-BCL C++ Example Problems =============================== file xbdlvriis2rep.cxx `````````````````````` Transportation problem (infeasible data). Repairing infeasibility. - Using Optimizer functions - (c) 2008-2023 Fair Isaac Corporation author: S.Heipcke, Jan. 2008, rev. Mar. 2011 ********************************************************/ #include <iostream>
#include <cstdio>
#include <cstring>
#include "xprb_cpp.h"
#include "xprs.h"

using namespace std;
using namespace ::dashoptimization;

#define NSupp 10                  // Number of suppliers
#define NCust 7                   // Number of customers
#define MaxArcs 100               // Max. num. of non-zero cost values

#define VANFILE XPRBDATAPATH "/delivery/ifvan.dat"    // Van data file
#define COSTFILE XPRBDATAPATH "/delivery/cost.dat"    // Cost data file

void printsolution(XPRBprob &p, int scode, XPRBvar x[][NCust]);
void printsolution2(XPRSprob op, int scode, XPRBvar x[][NCust]);

/****DATA****/
// Supplier:      London  Luton  B'ham Bristl  Derby Stckpt   York
double SUPPLY[] = {140.0, 200.0,  50.0,  10.0, 400.0, 200.0,  20.0,
// Supplier:       Derby  Soton Scnthp
                   90.0,  30.0,  12};
// Customer:       London Livpol Doncst   York   Hull  Manchr Shffld
double DEMAND[] = {1230.3, 560.4, 117.1, 592.8, 310.0, 1247.0,  86};

double COST[NSupp][NCust];        // Cost per supplier-customer pair

double IFVAN[NSupp][NCust];       // Non-zero if route uses vans instead 
                                  // of lorries
double VANCAP=40;               // Capacity on routes that use vans

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

void modDelivery(XPRBprob &p)
{
 XPRBexpr lobj, lc;
 XPRBctr ctr, CSupply[NSupp], CDemand[NCust];
 int s,c;
 XPRBvar x[NSupp][NCust];

 int ncol, nrow, scode;
 double *lrp, *grp, *lbp, *ubp;

 XPRSprob op;
  
/****VARIABLES****/
 for(s=0;s<NSupp;s++) for(c=0; x[s][c]=p.newVar(XPRBnewname("x_s%d",s)); for(s=0;s<NSupp;s++) Objective: Minimize total cost lobj +=COST[s][c]*x[s][c]; Set objective function Satisfy demand of each customer lc=0; CDemand[c]=p.newCtr("Demand",>= DEMAND[c]);
 }
 for(c=4; c<NCust; Satisfy demand of each customer lc=0; for(s=5;s<NSupp;s++) +=x[s][c]; CDemand[c]=p.newCtr("Demand",>= DEMAND[c]);
 }
        
 for(s=0;s<5;s++)                 // Keep within supply at each supplier
 {
  lc=0;
  for(c=0; c<4; c++)  lc+= x[s][c];
  CSupply[s] = p.newCtr("Supply", lc <= SUPPLY[s]);
 }          
 for(s=5;s<NSupp;s++) Keep within supply at each supplier lc=0; for(c=4; lc+=x[s][c]; CSupply[s]=p.newCtr("Supply", <=SUPPLY[s]); for(s=0;s<NSupp;s++) if(IFVAN[s][c]!=0) Set objective sense to minimization Solve the LP-problem cout <<="LP status: " if (p.getLPStat()==XPRB_LP_OPTIMAL) Get value else IIS op=p.getXPRSprob(); Retrieve Optimizer problem Trying fix infeasibilities lrp: (affects=and ax aux_var=b grp:>= rows)
   ax + aux_var  = b 
   ax + aux_var >= b
lbp:
   x_i + aux_var >= l
ubp:
   x_i - aux_var <= u 
*/

/**** Simplified infeasibility repair:
      specifying preferences per constraint/bound type ****/
  cout << "\n**** Repair infeasibility:" << endl;
  XPRSrepairinfeas(op, &scode, 'c', 'o', ' ', 10, 9, 0, 20, 0,001);
  printsolution2(op, scode, x);         /* Print out the solution values */

/**** Weighted infeasibility repair:
      specifying preferences for every constraint/bound separately ****/

  XPRSgetintattrib(op, XPRS_ORIGINALCOLS, &ncol); 
  XPRSgetintattrib(op, XPRS_ORIGINALROWS, &nrow); 
  lrp = new double[nrow]; 
  grp = new double[nrow]; 
  lbp = new double[ncol]; 
  ubp = new double[ncol]; 
  memset(lrp, 0, nrow*sizeof(double));
  memset(grp, 0, nrow*sizeof(double));
  memset(lbp, 0, ncol*sizeof(double));
  memset(ubp, 0, ncol*sizeof(double));

/* Relax bounds due to van capacity */
/* Repairweightedinfeas for upper bounds of concerned flow variables */

  for(s=0; s<NSupp; for(c=0; if(IFVAN[s][c]!=0) ubp[x[s][c].getColNum()]=20; cout <<="\n**** Relax van capacity:" ubp,='d' 0.001,="" Relax supply limits buy in additional Repairinfeas for='less or equal' side of Supply constraints for(s=0; lrp[CSupply[s].getRowNum()]=10; demand not satisfy all Demand grp[CDemand[c].getRowNum()]=9; delete Read data from files void FILE int Initialize tables to COST[s][c]=0; IFVAN[s][c]=0; the file datafile=fopen(COSTFILE,"r"); 99,="g," van Print out solution values XPRBvar double const char *rstat[]={"relaxed optimum found",="relaxed problem infeasible" ,="relaxed problem unbounded" if(scode==0)>0,01)
     cout << x[s][c].getName() << ":" << x[s][c].getSol() << " ";
  cout << endl;    
  cout << "Violations:" << endl;
  for(c=0; c<NCust; sup=0; for(s=0; sup+=x[s][c].getSol(); cout <<=" Customer " c dem=0; for(c=0; dem+=x[s][c].getSol();>SUPPLY[s])
    cout << " Supplier " << s << ": " << dem-SUPPLY[s] << endl;
  }
  for(s=0; s<NSupp; for(c=0; if(IFVAN[s][c]!=0 cout <<=" Van " s c void int XPRBvar double const char *rstat[]={"relaxed optimum found",="relaxed problem infeasible" ,="relaxed problem unbounded" if(scode==0) sol=new Get the solution values for(s=0;>=0 && sol[x[s][c].getColNum()]>0,01)
     cout << x[s][c].getName() << ":" << sol[x[s][c].getColNum()] << " ";
   cout << endl;    
  cout << "Violations:" << endl;
  for(c=0; c<NCust; sup=0; for(s=0;>=0) sup+=sol[x[s][c].getColNum()];
   if(sup<DEMAND[c]) cout <<="  Customer " c for(s=0; dem=0; for(c=0;>=0) dem+=sol[x[s][c].getColNum()];
   if(dem>SUPPLY[s])
    cout << "  Supplier " << s << ": " << dem-SUPPLY[s] << endl;
  }
  for(s=0; s<NSupp; for(c=0; if(IFVAN[s][c]!=0>=0 &&
       VANCAP<sol[x[s][c].getColNum()]) {
     cout << "  Van " << s << "-" << c << ": ";
     cout << sol[x[s][c].getColNum()]-VANCAP << endl;
    } 
 }
}

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

int main(int argc, char **argv)
{
 XPRBprob p("Delivery");          // Initialize a new problem in BCL
 readData();                      // Data input from file
 modDelivery(p);                  // Problem formulation and solution

 return 0;
}