change data and freeze solution in loop

Question

Thank you for your reply, Alex.

but Let me ask my question more precisely.. I have this data string

{string} N = {"a", "b", "c", "d", "e", "f", "g"};

and I have to get one of the arrays from N in each iteration in cplex loop, for example, in iter 1 I have to get N = {"a"} and for the next step I have to get N = {"a", "b"} and I must continue in the same way; The rest of the data is constant in all iteration. And in each iteration, I have to save the solution of this iteration for the next step.

my data:

{string} N = {"a", "b", "c", "d", "e", "f", "g"};

{string} M = {"aa","bb","cc","dd","ee"};

range nods = 0..10;

tuple edge{

int o;

int d;

float C;

float D;

};

{edge} edges = ...;

int Tr = ...;

int cd = ...; . . .

my variables:

dvar boolean x[M][N];

dvar boolean y[M,edges];

dvar boolean w[M,N,edges];

dvar float+ T[M][nods];

I apologize for the frequent and long questions.

please help me :( thank

Answer 1

For modifying a set and solving again the same model you can see

https://github.com/AlexFleischerParis/howtowithoplchange/blob/master/changeset.mod

{int} s={};

    main {
      var source = new IloOplModelSource("subset.mod");
      var cplex = new IloCplex();
      var def = new IloOplModelDefinition(source);
     
     
      for(var k=1;k<=5;k++)
      {
      var opl = new IloOplModel(def,cplex);
        
      var data2= new IloOplDataElements();
     
    data2.y=thisOplModel.s;
    data2.y.add(k);
      opl.addDataSource(data2);
      opl.generate();

      if (cplex.solve()) {
         writeln("OBJ = " + cplex.getObjValue());
      } else {
         writeln("No solution");
      }
    data2.end();
     opl.end();
     
     
    }  
     
    }

with subset.mod

{int} y=...;

execute
{
writeln("y=",y);
}

dvar float x;

maximize x;
subject to {
  x<=sum(i in y)i;
}

execute
{
writeln("x=",x);
}