Salve. Qualcuno potrebbe controllare il mio file??? Non rieasco a capire perchè l'orario non si chiude e qual è il vincolo che impedisce al mio orario di funzionare. C'è sempre l'attività dello stesso insegnante che non riesce a trovare spazio .... Allego il file affinchè qualcuno possa verificarlo.
Grazie a chi vuole darmi suggerimenti
I generated on 8 threads and I obtained in about 3 minutes a solution. I attach it.
Thank you Liviu so much. I wonder why I couldn't get it? There was any conflict or something wrong on settings? Any suggestions for the future?
You are welcome, Scibo! It is your original file, I just generated on 8 threads and the chances are better to finish successfully. If you have 8-core processor, generate multiple on 8 threads. I have 8 cores and 16 threads (Ryzen 2700X), and I usually generate on 8 threads in FET multiple.
I saw these in your file:
1) Teachers max 1 gap per day and a teacher had particularly max 2 gaps per day. This teacher's constraint is useless. You might need to add 1 for each teacher (with a single click in FET) and modify for that particular teacher to 2 instead of 1.
2) I don't know why you used activities max hourly span (of course, if you know what this constraint does, it is OK).
Thanks a lot! So with a i7 Intel Core how many threads you can suggest in order to speed up or to have more chances?
FET knows the number of threads, for instance in my case 16, and the maximum allowed threads to generate multiple with FET on my computer is 16. But this 16 is not the number of cores, which is 8. You need to read what is cores and what is threads of a processor.
@Volker Dirr can answer better.
Probably you have 4, 8, or 12 cores, and FET will allow maximum 8, 16, or 24 threads, respectively. You need to search your exact processor on the internet and read the specifications. I would advise you to use the number of cores, but Volker might prefer to use the number of threads.
If unsure, use maximum FET allows, or half of them if the CPU temperature gets too high with full.
I found on the internet that my i7 has 12 cores. So how many timetables I can generate with multiple generation option?
You can generate on 12 FET threads. The first thread to finish will be the first timetable.
THANKS
I've been trying again and again with the same file but it doesn't work except for yours. How can I manage the seed? It might help?
If you input the exact same random seed and generate single on the same file, the result will be duplicated. So, you can duplicate my generation, if you would like.
But in usual generations please keep the seed different.
You can try generate multiple with time limit of 10 minutes. And generate 1000 timetables.
Perfect
Liviu, I'm very sorry. Could you please try to close this timetable? i can't succeed ...
No problem, Scibo, I'll try. Should I only try on your exact file, or may I make it easier on some constraints?
Could you try both? :-)
OK, I will try both :)
I corrected the max gaps per day and per week for the teachers, and I obtained a timetable. I attach the files.
For these 6 teachers: Ingria S, Grasso S, Finicchiaro R, Paterno C, Virgilio E, and Lanzafame Alfredo I put 3, 3, 6, 3, 3, 3 max gaps per week, and the rest of the teachers have max 2 gaps per week.
For Finocchiaro R (I think) I made max gaps per day = 2, and the rest of the teachers have max 1 gap daily, and some have max 0.
EDIT: The max gaps per day is 1 for everybody, I forgot to deactivate the constraint. But this way the solution is even better.
EDIT 2: I will let it overnight to generate, on your unmodified file. I'll tell you in the morning if I got a solution.
I have two solutions to your original file, attached.
Thanks a lot, especially for your settings tips.... Have a good night
Hello Liviu. I had to do some adjustments but now my timetable can't find a solution. Could you try with your super powerful PC if you can find a solution?
Hello, Scibo,
I will try to generate (but I think your computer is better :) ). If it is impossible, should I try to make it easier?
I asked you previously if your activities max hourly span is correct, and what is it for, but you did not answer.
Max 6 Hours at school but five lessons and 1 hole
If it is impossible you can make it easier for sure
Quote from: scibo@tin.it on September 10, 2025, 05:07:07 PMMax 6 Hours at school but five lessons and 1 hole
Do you mean you used activities max hourly span to ensure this? This would be a misunderstanding. I tried deactivating all these constraints and it solves easily. I attach the first solution and my modified file. This activities max hourly span constraint means a totally different thing.
What max hourly span means? And how can ensure that the maximum staying at school must be 6 hours (5 + 1 hole)?
Max hourly span is a kind of peculiar constraint, requested by a user, and I didn't quite like it, but it is needed in some cases. Say (A1, A2, A3), max hourly span = 2 -> then these 3 activities can be on any days, but the hours they occupy must be maximum 2 continuous if we make abstraction of the days, like: A1->Monday 1, A2->Tuesday 2, A3->Friday 1. A3 cannot be on Friday 3, because then the hourly span would be 3.
You should add teachers max 5 hours daily and teachers max 6 span per day.
I apologize!