Hello,

I am currently migrating the optimization model from CPLEX OPL to CPLEX Concert with Java.

I would like to know how to define decision variable using tuple definition.

In CPLE OPL, I defined the decision variable as below.

tuple Index{
     int studentID;
     int offeringID;
}
{Index} X= {<s, o> | s in Students, o in offerings}

In order to define the decision variable X in Java & CPLEX Concert, I defined class structure and decision variable as below.
class INDEX{
   int studneID;
   int offeringID;
}
List<INDEX> indexes = new ArrayList<INDEX>();
IloNumVar[] X = cplex.numVarArray(indexes.size(), 0, 1, IloNumVarType.Int);

I would like to have the constraint such as cplex.addEg(cplex.sum(X[indexes]), 1), but it didn't work.

Would you please help me how to describe the decision variables with tuple in Java & Cplex?

Thank you for all your help!

------------------------------
Sung Hwang
------------------------------

#DecisionOptimization

This is basically a duplicate of this question.

------------------------------
Paul Rubin
Professor Emeritus
Michigan State University
------------------------------

Original Message:
Sent: Wed June 02, 2021 11:06 PM
From: Sung Hwang
Subject: Tuple Index in Java & CPLEX Concert

Hello,

I am currently migrating the optimization model from CPLEX OPL to CPLEX Concert with Java.

I would like to know how to define decision variable using tuple definition.

In CPLE OPL, I defined the decision variable as below.

tuple Index{
     int studentID;
     int offeringID;
}
{Index} X= {<s, o> | s in Students, o in offerings}

In order to define the decision variable X in Java & CPLEX Concert, I defined class structure and decision variable as below.
class INDEX{
   int studneID;
   int offeringID;
}
List<INDEX> indexes = new ArrayList<INDEX>();
IloNumVar[] X = cplex.numVarArray(indexes.size(), 0, 1, IloNumVarType.Int);

I would like to have the constraint such as cplex.addEg(cplex.sum(X[indexes]), 1), but it didn't work.

Would you please help me how to describe the decision variables with tuple in Java & Cplex?

Thank you for all your help!

------------------------------
Sung Hwang
------------------------------

#DecisionOptimization