Originally posted by: Janisch

Hello,

I would like to know what problem CPLEX expects?

I tried to paste this into the mod.file. But I think my orders are not right yet.

execute {
   writeln(isMIP());
   writeln(isQC());
   writeln(isQO());
   writeln(isLP());
};

Are there any other problem classes?

Thank you for your help.

How is this related to callbacks?

Also, what exactly is your problem? This should be all problem classes, at least I don't see anything missing right now.

Originally posted by: Janisch

I just want to know with which problem CPLEX works. So what value is true or false.

And you get false for all 4?

Originally posted by: Janisch

It doesnt work.

"the element isMILP is not present in the olp model"

The methods you are using are instance method of the IloCplex class (this should be clear from where they are documented). So you need an instance of the IloCplex class to invoke them. Try 'cplex.isLP()'.

I am not sure what is the correct place to invoke these functions (the model must have already been generated for these functions to return the correct thing). Maybe ask on the forum dedicated to OPL.

On the other hand, are you writing some generic code? Otherwise I would expect that you perfectly know what the type of your problem is? CPLEX is not going to magically change that.

Originally posted by: Janisch

Thank you! I forgot to use the cplex.class. Now it's working.