Originally posted by: SystemAdmin

I have used the following c++ code to access the value of Excess which was declared as dexpr in opl.

IloOplElement ExcessElement = opl.getElement("Excess");
IloNumExprArg ExcessExpr = ExcessElement.asNumExpr();
Excess = cplex.getValue(ExcessExpr);

However, I got an error message from these statements:
concert exception: ILoExtractable 826 IloNumVarI has not been extracted by Iloalgorithm ...

What did I do wrong? Suggestions please.
#CPLEXOptimizers
#DecisionOptimization

Originally posted by: SystemAdmin

This exception is thrown if you try to read the value of a variable that does not appear in the model. Do you have any such variables in your dexpr? Does it help to add a dummy constraint like "Excess >= -LARGE_VALUE" to the model, so that the dexpr (and all variables in it) are guaranteed to be in the model?
#CPLEXOptimizers
#DecisionOptimization