Originally posted by: rNeo

Hello, I have a straightforward (I hope) issue that I have been grappling with all day. I am trying to name a 2D decision variable in C++ using concert technology. My model is a real life assignment problem - so I need to index my variables with the actual resource and task names in order to provide the solution to the decision makers. This is easy with OPL using tuples. However, I am confused with concert technology. I have 2 decision variables (a) a 2D variable boolean variable that indicates which resource has been assigned to which task, and (b) a 1D boolean indicator variable that indicates if a particular resource has been selected in the assignment solution.

It has been straightforward to name the 1D variable. I have the following Map which holds the name of the resources and their experience levels. I use this Map to iterate the variable and name it as follows:

map<string, string> Map;       // The first string holds the name and the second string the experience level

               Y.add(IloNumVar(env, 0, 1, ILOINT, convertedName));

So how do I do the following for the 2D variable. It is of the form Xij where i is the Resource Name and j is the Task Name. I have declared the variable as follows:

IloArray<IloNumVarArray> X;

I have another Map which indicates the fit between i & j. It is:

Map<string, map<string, float>> fitMap; //first string is the resource name, second string is the task name and the float is the fit value.

Any ideas will be very appreciated!

Something like this should do the trick:

for (map<string,map<string,float> >::const_iterator it = fitMap.being(); it != fitMap.end(); ++it) {
   IloNumVarArray tmp(env);
   X.add(tmp);
   for (map<string,float>::const_iterator jt = it->second.begin(); jt != it->second.end(); ++jt) {
      char convertedName[...];
      // Create the convertedName
      ...
      tmp.add(IloNumVar(env, 0, 1, ILOINT, convertedName));
   }
}

Also note that the instantiation of X in your code lacks an 'env' argument. It should be

IloArray<IloNumVarArray> X(env);

Originally posted by: rNeo

Thank you very much, Daniel! My apologies for the late reply. I tried it out and it works perfectly. Thanks again!