Originally posted by: Y9AX_Pooyan_Kazemian

Hi,

I describe My problem with an example. Suppose we want to write the following in CPLEX:

Sum(i from 5 to 10) sum(j form 1 to i) x_ij <= 100

The problematic part is the second summation that goes from 1 to i.

In CPLEX I write:

forall (i in 1..10 , j in 1..i) const: x[i][j]<=100;

It returns the following error:

“Constraint labeling not supported for dimensions with variable size, use named constraints instead.”

There should be a way to write the summation when it’s dependent to the preceding summation. Any help is appreciated?

Thanks,
Pooyan
#DecisionOptimization
#OPLusingCPLEXOptimizer

Hi,

in documentation

IDE and OPL > Optimization Programming Language (OPL) > Language Reference Manual > OPL, the modeling language > Constraints > Constraint labels

you can find an example:

tuple RangeTuple
{
    int i;
    int j;
    string k;
};
{RangeTuple} RT = {<1, 2, "bla">};
 
{int} s={1,2};
 
constraint rangeLabel[RT][s];
 
minimize 1;
 
subject to
{
    forall(<p1, p2, p3> in RT)
        forall(i in p1..p2)
    rangeLabel[<p1,p2,p3>,i]:
     1 == 1;
}

Regards

Alex
#DecisionOptimization
#OPLusingCPLEXOptimizer