Binary variables are usually faster than SOS1 sets, especially when the solver can apply some good cuts.Of course here are cases that can be modeled with SOS1 sets and not with binary variables, but that is not what you are dealing with..
---------------------------------------------------------------- Erwin Kalvelagen Amsterdam Optimization Modeling Group [email protected] https://www.amsterdamoptimization.com <https://amsterdamoptimization.com> ---------------------------------------------------------------- On Tue, Mar 15, 2022 at 6:48 AM Tommaso Cucinotta < [email protected]> wrote: > Hi, > > I'd like to know whether Mathprog supports (or is there any plan to > support) SOS (special ordered sets) variables, at > least type 1. > > I often use mathprog and glpsol to convert MILP problems (actually, BLP > mostly) for other solvers (CBC, CPLEX), and I'm > seeing these other solvers support these types of variables, what makes me > think that there might be some advantages in > formalizing a problem this way, as perhaps the solver might be quicker in > scanning through the possible branches etc... > I mean, using the SOS1 native formalization, instead of equivalent > formulations as in > > https://en.wikibooks.org/wiki/GLPK/Modeling_tips#Special_ordered_sets > > Thanks, > > T. > > -- > Tommaso Cucinotta, Computer Engineering PhD > Associate Professor at the Real-Time Systems Laboratory (ReTiS) > Scuola Superiore Sant'Anna, Pisa, Italy > http://retis.sssup.it/people/tommaso > > >
