New features Min gaps between an ordered pair of activity tags for all Students

[henriquebelo]

Hello,

How can I make a gap with this constraint with differents students set?

I used the tag EDF-5e6 with EDF-SEC and EDF-SEC with EDF-5e6.

The studends set are different so this don't work.

How can I solve this issue? In a simple way.

Best Regards

[Liviu Lalescu]

1) Could you please send me your file? Here, archived, if necessary, or privately by email.

2) The constraint min 1 gaps between ordered pair adds an extra hour between first tag and second tag. If I understand correctly, you need the tags only not to be overlapped on the same hour?

3) I think a solution for (2) is to add some dummy students sets or teachers, and add them in your data in a duplicate way, so that the activities of groups say 5B and 12A cannot overlap (add for instance dummy students set 5B_12A to both these groups). But I need to see your data.

4) There might be other methods using FET official. If everything else fails, I think it is easy for the algorithm to add for you a custom constraint (tedious to add in the interface for me).

[henriquebelo]

Thank your for your fast answer.

1) I send you by private message.

2) Exactly, I need the tags only not to be overlapped on the same hour. (how can I do this with dummy students set? I didn't understand)


I think there is a good new feature to add for future releases

A set of activities are not overlapping between an ordered pair of activity tags. No?

Best Regarsd

[Liviu Lalescu]

You need to send me an email, because forum private messages do not allow attachments. You can find my email address on the FET homepage or on my personal homepage.

I will explain you by adding the dummy subgroups in your file, if it is possible, and sending you back the file.

I will think of your proposal, if dummy subgroups cannot solve the problem reasonably.

[Liviu Lalescu]

Thank you for your suggestion! I think it needs to be implemented and I hope others can benefit as well.

It cannot work with dummy students sets, the idea fails, because you have too many subgroups and you have the students early constraints (I thought for instance you can add a dummy students set to 5A and the same students set (dummy) to 12A, and this way their activities cannot overlap. But: a) too many dummy students sets and b) bad idea, because you only want the specific activity tags not overlapping, not all the activities of 5A and 12A).

It is possible with activities not overlapping constraints, but you need to add too many constraints.

So, I think I will add the constraint "activity tags not overlapping". Or should it be "pair of activity tags not overlapping"? (the first variant allowing say 4 tags, and each pair between them cannot overlap, so it includes the second variant, if you only add 2 tags).

Other users, please let us know your opinion.

[Volker Dirr]

Maybe we will get other/better ideas if we know why you need that feature. So what is the idea? Why do you need a gap between them if they don't share teachers, students and rooms.

[henriquebelo]

We need this feature to use on gym activities.

We don't want a mix of young and old students on the gym activities at same time, because on the shower room is embarrassing situation for the younger students.

We can manage this situation but we need to make about 200 constrains...

Best Regards

[Volker Dirr]

ah. ok. i see.

in that case i think it is maybe a bad idea to do it that way, since it is difficult to use the gap slot. so it might be empty (or with pupils middle age only).

In that situation i guess is might be much better to do it different. How about a rule like
allow monday only sport for 5th/6th grade
tuesday only sport for 7th/8th grade
...
by that they are not mixed and there is also no unused empty gym duraing the gap.

[Liviu Lalescu]

No, Volker, he suggests constraint "activity tags not overlapping" (not min 1 gap between them). It should be a very useful constraint, also in maybe other cases in which you have two sets of activities and no activity from the first set can overlap with an activity from the second set, but the activities from the first set may overlap, and the activities from the second set may overlap.

I think there was at least another user suggesting this in the past, but cannot remember for sure.

[Volker Dirr]

ok. but as long as the constraint is not present (not easy to enter) my suggestion might still be a possible solution to solve the problem if he needs results right now.

[Liviu Lalescu]

I have a design problem: in the shortcut buttons in Time tab, there misses the "Tags" constraints. Should I:

1) Add a button "Misc", and it shows "Break" and "A set of activity tags are not overlapping", or

2) Add "A set of activity tags are not overlapping" in the "Activities" section of time constraints, after "A set of activities are not overlapping"?

[henriquebelo]

The 2) suggestion is the right answer for our problem, that we can manage with 2 activities tags.

[Liviu Lalescu]

I made it, there is a snapshot here for now: https://lalescu.ro/liviu/Backup-fet/

Please report any bugs.

I will test some more later today.

[Liviu Lalescu]

I corrected some things. I have put a new snapshot in the usual test location ( https://lalescu.ro/liviu/fet/download/test/ ) and announced it on the snapshots section of the forum.

Thank you for the suggestion!

[Liviu Lalescu]

I just released the new official version 5.39.0, with this constraint. Thank you for your suggestion and testing!