cplexconstraint-programmingoplcp-optimizer

guide me to write a capacity constraint

I am trying to add few more constraint with existing  resource constraint project scheduling problem available OPL examples. Here I am attaching the example files of RCPSP problem. At present in this example problem I can start as many tasks as possible based on resource capacity. I want to add an additional constraint on maximum number of tasks performed in an interval variable should be less than or equal to 5. In other words simultaneously I can't do more than 5 tasks at a time.

The example problem can be located in OPL at examples/opl/sched_rcpsp

Solution

  • You could use cumul function.

    Before the subject to block you could write:

    cumulFunction nbTasks = 
   sum(t in Tasks) pulse(itvs[t],1);

    And then in the subject to block you simply add:

    nbTasks<=5;