On Wed, 2017-08-02 at 16:11 -0400, Peter Quincy Ng wrote: > Hello, > Thank you for your previous response it was quite helpful. I am having > trouble with another problem and wasn't able to find this in the GLPK > GNU manual. > > So, I have a contract scenario where I want to start and end contracts > to meet demand. My problem is that I want to list the long-term > contracts so that meet demand over several days, but cannot be started > on certain days, so the value for long-term will be zero. > > So I have this dataset: > > set DATES := > > 4.01 > 4.02 > 4.03 > 4.04 > 4.05 > 4.06 > 4.07 > 4.08 > > And have the following demand: > > param NumDemand := > > 4.01 0 > > 4.02 1 > > 4.03 5 > > 4.04 2 > > 4.05 0 > > 4.06 1 > > 4.07 9 > > 4.08 12 > > So I have a constraint where short-term contracts and long-term > contracts must meet demand so: > > ShortTerm + LongTerm >= NumDemand > > But long terms can only start on 4.03 to 4.06, so I need to put the > values for 4.01, 4.02, 4.07 and 4.08 when I optimize.
I think you need to define two sets of dates: one for long-term and other for short-term contracts, and then use them as indexing sets. [Please post your questions to the help-glpk list, not to me.] > > I hope that makes sense, > > Thanks, > Peter > _______________________________________________ Help-glpk mailing list [email protected] https://lists.gnu.org/mailman/listinfo/help-glpk
