set only one lesson on saturday

[gt]

Hello. In our Academy we avoid lessons on Saturday but not in any case.
I have set a break on Saturday to exclude that day from timetabling.
Now it happens that I have to place just one lesson on Saturday.
I'm going to set "teacher's not available time" on Saturday for all teachers except one (I don't want FET placing other lessons on Saturday).
Is there a quick way to do this without adding a lot of new constraints?

Thanks in advance for your help.

[Volker Dirr]

Did you already have a generated timetable and only need to fix that?

Then it might be only needed to move that single activity. No need to set not available times, since all times are fixed.

If you haven't generated yet, then it might easier to set available times for years/groups. But that is depending on your dataset.

A 3rd variant might be deactivating the that saturday activity. And set break on Saturday. Then generate a timetable. Now open the timetables from the results timetable, remove the break on Saturay, activate the activity and generate again (generate will take just a second, since nearly all times and rooms are fixed)

A 4th variant is similar to 3rd one, just use TiTiTo to modify.

[Liviu Lalescu]

My idea would be for you to add two constraints:

1) A constraint activities occupy max time slots from selection, selection = Saturday, activities = all activities, max occupied = 1;

and

2) A constraint activities max simultaneous in selected time slots, selection = Saturday, activities = all, max simultaneous = 1.

In the Block planning mode there is the constraint "Max activities from a set in selected time slots", but at the time we added that constraint we decided it is not useful in other modes.

Please let me know if my approach with the 2 constraints above works, I am interested.