[Help-glpk] Trouble with integer variables

[IgorArbizu]

Hi All;
First of all, I must say I'm  a
newbee to linear programing and GLPK.
I want to solve a problem forcing the
sctructural variables to be integer, but the result has no
integers, using simplex o interiro point.
I´m using the java interface to 4.8 version.

Here's the code:


GlpkSolver solver = new GlpkSolver();
               
         
      solver.setObjDir(GlpkSolver.LPX_MAX);
         
      solver.setClss(GlpkSolver.LPX_MIP);
         
      solver.addRows(auxVars.length);
         
      for (int i = 1; i <= auxVars.length; i++)
{
         
              solver.setRowName(i,
"p" + i);
         
              solver.setRowBnds(i,
GlpkSolver.LPX_UP, 0, auxVars[i - 1]);
         
      }
         
      solver.addCols(objCoefs.length);
         
      for (int j = 1; j <= objCoefs.length; j++)
{
         
              solver.setColName(j,
"x" + j);
         
              solver.setColKind(j,
GlpkSolver.LPX_IV);
         
              solver.setColBnds(j,
GlpkSolver.LPX_DB, 0, 17);
         
              //solver.setColBnds(j,
GlpkSolver.LPX_LO, 0, 0);
         
              solver.setObjCoef(j,
objCoefs[j - 1]);
         
      }
         
      //int n=constrCoefs.length*constrCoefs[0].length;
         
      
         
      int nonzeroscounter=0;
         
      for(int k=0;k<constrCoefs.length;k++){
         
              for(int
m=0;m<constrCoefs[k].length;m++){        
               
       
         
               
      if(constrCoefs[k][m]!=0.0) nonzeroscounter++;
               
               
       
         
              }
         
      }
         
      System.out.println("nonzeroscounter..."+nonzeroscounter);
         
      int ia[]= new int[nonzeroscounter+1];
         
      int ja[] =new int[nonzeroscounter+1];
         
      double ar[]= new double[nonzeroscounter+1];
         
      int index=0;
         
      for(int k=0;k<constrCoefs.length;k++){
         
              System.out.println("k..."+k);
         
              for(int
m=0;m<constrCoefs[k].length;m++){
         
               
      System.out.println("m..."+m);
         
               
      if(constrCoefs[k][m]!=0.0){
         
               
      ia[index+1]=k+1;
         
               
      ja[index+1]=m+1;
         
               
      ar[index+1]=constrCoefs[k][m];
         
               
      index++;
         
               
      System.out.println("index..."+index);
         
               
      }
         
               
      
         
               
              
         
              }
         
      }          
     
         
      solver.loadMatrix(nonzeroscounter, ia, ja,
ar);
         
      solver.simplex()

and the solution is:
x1=3.333333333333333
x2=6.666666666666667
x3=0.0
so, not integers at all, any suggestions????
Thanks in advance

Igor