[Help-glpk] Newbie scheduling problem question, contiguous time interval constraints

[Roland Roberts]

I'm a newbie to MILP and am stuck on specifying what I think should be a 
pretty common problem. I'm trying to solve a student class scheduling 
problem for a middle school. I can formulate parts of the problem, but 
am drawing a blank on connecting everything. I'm willing to pick up both 
manuals and texts if someone can point me to ones that should be helpful.

The basic problem is that I classes c, student groups g, time periods p, 
and days d. We're breaking each day into 15-minute "modules" which have 
to be schedule. A class has to span 3-8 modules on any give day. Some 
classes have a minimum number of modules per week that have to be 
completed. With just the above, I can specify the constraints by 
thinking of this as a 4-dimensional array X[c,g,p,d] and the constraints 
are various sums. The problem I run into is specifying the the 
continuity constraint on scheduling. It's not sufficient to have 3 
modules for class C1, they have to be 3 contiguous modules.

How do I specify this sort of thing?

roland

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