Time constraint

[Kudakwashe]

Dear fellow members. I am new in FET but i managed to develop a running timetable for our Campus (For a University). The problem i have is that some courses say A have two lessons per week, 2 hour lesson and 3 hour lesson. However the Three hour lesson must be in the afternoon always as its a practical. Can i achieve this by using the constraint a set of activities has a preferred time slot, then do one course by course or there is one catch all approach to this? Also need to understand the role of locking (Time and space constraints) what is the purpose thereof

[Liviu Lalescu]

I think you can use constraint activities preferred time slots, or subactivities preferred time slots. You can add activity tags to this activity of duration 3.

The locking constraints are for locking specific activities to specific time slots and rooms.

Maybe others can answer better.

[Kudakwashe]

Thanks for the prompt response.  Let me try and see how it will work. Locking after generating ensures that further re-running do not alter the time and room allocation of the previous or what?

[Liviu Lalescu]

Locking after generating ensures that further re-running do not alter the time and room allocation of the previous or what?

Yes. If you lock all the activities, the timetable will be generated instantly then.

[Volker Dirr]

you might not need to tag activities with duration 3. you just might use the activities preffered starting time constraint and check the "duration" checkbox (of course increase up to 3).
similar to activities with duration 2.
But that depend of your on your data. you might to do that in combination with the subject.