Sum only for elements less than N

Question

I want to add the following constraint:

@addConstraint(m, sum{sum{x[:alpha, d, s], s in S}, d in D} >= 5)

where x is a decision variable and

D = [1:50]

but I want the sum to be calculated only for d less than 10.
Is there a built-in way or do I have to find some workaround?

Answer 1

Should be able to just do d in D; d < 10, i.e.

@addConstraint(m, sum{sum{x[:alpha, d, s], s in S}, d in D; d < 10} >= 5)

For completeness, here is the link to the relevant section of the manual, which could be structured better. We'll work on that!