Min days/week

[Benahmed Abdelkrim]

Hello!
I was working on a file for which I needed a constraint: min days (days of FET = half days)) per week for a teacher(s). the max days(half days) constraint exists but min days does not. can we add it if you want of course. thanks in advance. 

[Liviu Lalescu]

I want, but it is very difficult.

From the existing TODO:

"- Students (set) min half-days per week (suggested by Abdeljalil Elghazoui) - but is it needed, considering we have available min mornings/afternoons and min hours daily without allowing empty real days?"

Are you sure it is really needed, considering this?

[Liviu Lalescu]

Could you please tell me how is it needed this constraint? For a regular file, or for some tricks?

[Benahmed Abdelkrim]

I would like all teachers to work 7 half days a week. FET has almost made this condition except for 1 teacher(T3) where he had 6 half days / week.

see attached file below ...

[Liviu Lalescu]

It is very very complicated. But if it is very much important to you and others, I will try it.

Tomorrow I will go to the countryside, without computer and with internet only on my phone, and it will be harder to answer. Maybe for a week, maybe less.

[Benahmed Abdelkrim]

 I have thought about this. you can ignore this suggestion.  it's not important. I fear that with this constraint the solution could become impossible.  so don't worry and enjoy your day 🙂

[Liviu Lalescu]

OK, Benahmed, I'll think about it. Thank you!

[Benahmed Abdelkrim]

🙂

[Liviu Lalescu]

Dear Benahmed,

I will try this constraint, maybe tomorrow. Please let me know if you can help me with testing intensively with combinations of constraints.

[Benahmed Abdelkrim]

Hello dear Liviu;
 Yes of course I can help. Thank you very much for your interest 🙂

[Liviu Lalescu]

Hello, Benahmed,

It is done: https://lalescu.ro/liviu/fet/download/test/

The core part took only 1 hour to implement.

On your file it is impossible, you need to change something.

I hope to release very soon, maybe even tomorrow. So please test soon.

Please test:

1) Old files without the new constraint, complex files, with and without min hours daily/per real day, max gaps per day/week/afternoon, min real days per week. Start with the same random seed, the ending random seed should be the same with 6.5.3 and 6.5.4-snapshot.

2) Test the new constraint with complex files, as above, to check it works.

[Liviu Lalescu]

Hello, Benahmed,

I optimized some things. No need to retest, but please continue testing with the newer snapshot (I just put a new snapshot in https://lalescu.ro/liviu/fet/download/test/ ).

[Benahmed Abdelkrim]

Hello, Benahmed,

It is done: https://lalescu.ro/liviu/fet/download/test/

The core part took only 1 hour to implement.

On your file it is impossible, you need to change something.

The cause is max afternoon/week.  if you disable this constraint or you put max afternoon=4 FET will produce fast..

[Benahmed Abdelkrim]

Hello, Benahmed,

I optimized some things. No need to retest, but please continue testing with the newer snapshot (I just put a new snapshot in https://lalescu.ro/liviu/fet/download/test/ ).

I did some tests with old files, everything seems OK. 🙂

[Liviu Lalescu]

Benahmed, I hope I reached a stable version: https://lalescu.ro/liviu/fet/download/test/

Please test with the new constraint only, to see if it solves: files with the new constraint, complex files, with and without min hours daily/per real day, max gaps per day/week/afternoon, min real days per week.

PS: Your file is not solvable even if I deactivate max afternoons.

I hope to release tomorrow afternoon (in about 24 hours from now), so please help me with testing.