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FET Support (English) => Get Help => Topic started by: flauta on March 11, 2023, 11:16:40 AM

Title: students set do not change room all together
Post by: flauta on March 11, 2023, 11:16:40 AM
My school is transitioning to scheme 'room for teachers' (students move) from the scheme 'room for students set' (teachers move) that is still the norm in Italy at the moment.

The building has rooms on two levels but only one staircase: so to avoid dangerous overcrowding of the staircase I must create a timetable in which only part of the students set change room at the end of an hour (let's say 5 sets change room on a total of 10).

Can someone suggest which constraints allow to get this result?

Thanks in advance
Andrea
Title: Re: students set do not change room all together
Post by: Liviu Lalescu on March 11, 2023, 11:47:30 AM
I think I understood now. Probably this cannot be done with the official FET as it is now, using the existent constraints.

I thought about it and it might be possible as a custom version, implementing a new constraint type.
Title: Re: students set do not change room all together
Post by: Volker Dirr on March 11, 2023, 12:50:20 PM
If you didn't use building constraints yet, you might just call floor 1 as building 1 and floor 2 as building 2 and then use building constraints.
Title: Re: students set do not change room all together
Post by: flauta on March 11, 2023, 01:18:30 PM
Thanks Liviu and Volker,

I already thought about calling floors as buildings: in my case going from building 1 to 2 would not need any empty slot: do the building constraints accept this situation?
Title: Re: students set do not change room all together
Post by: Volker Dirr on March 11, 2023, 07:19:27 PM
Yes. I assume the students doesn't have got gaps. So if there is no gap, the students can't change the floor.
In fact you might need to add "virtual gaps" with breaks.
For example if you have got hours 1 to 6 and there is a break between hours 2&3 and a break between 4&5 and always recommend to NOT add this break.
But in your situation it might be useful/needed to add those breaks. Since with whose breaks it is allowed for students to change the floor during the break.
Title: Re: students set do not change room all together
Post by: flauta on March 11, 2023, 08:09:35 PM
Thanks for the suggestions.

Students do not have any gaps, but some activities have even number of hours, say 2+2+1. And some activities can be split 1+1 in place of 2.

So I was thinking that some groups can do 1st hour in a room, then change and do 2nd and 3rd hour. Other groups can do 1st and 2nd hour and change between 2 and 3 (where we have the break too). And so on.

So maybe I only need a constraint saying: no consecutive room changes for the same group? How can I get it?

Or I could follow your advice and create alternate breaks (half groups after 2 4 6, others after 1 3 5) to split the number of groups by 2, so that only half of them move at a time.
Title: Re: students set do not change room all together
Post by: Liviu Lalescu on March 11, 2023, 08:16:28 PM
I was thinking of a possible new custom constraint, max n room changes at the end of each hour for all subgroups. Or maybe other customizations. But I could try to provide such a customization based on a work contract, if you or your institution are interested.
Title: Re: students set do not change room all together
Post by: flauta on March 12, 2023, 08:51:36 PM
Thank you Liviu, at the moment I'm only experimenting with a new timetable that will be used in September.
Title: Re: students set do not change room all together
Post by: Liviu Lalescu on March 13, 2023, 07:43:17 AM
Dear Andrea,

I thought about it. Since you offered so kindly to complete the Italian translation, I could try to add for you this customization completely free, if you are still interested.

If yes, I would need you to tell me if you want the constraint max n room changes at the end of each hour for the students or max n building changes. I would also need your input file.