Gurobi Python: how to write nested sum in a constraint

Question

I have an optimization problem and I\'m using Python and Gurobi to optimize it. In my problem formulation there is a constraint that has a nested sum.

constraint

Answer 1

Use two for statements inside the quicksum() function and two for statements in the generator expression:

mycts = m.addConstrs((quicksum(x[i,f,p]*y[i,f,p,t]
                               for i in I for p in P[i,f]) <= z[f,t]
                               for f in F for t in T), "myconstraint")

where m is your Model object.