[Help-glpk] help

[Daniele Micarelli]

Hi
 I have to solve a linear programming problem with the language and I'm planning mathprog
 I have difficulty writing the following constraint: ΣΣ r (i) * x (i, t) <= R
 where the first summation is true for all belonging to the W and the second summation has as its lower end t-d(i) and upper bound as t-1

 do you like I have to report to mathprog?

 I hope you understand the bond as written because I could not write it in a better way

 thanks