Hello all,
I have to organize an oral exam session for my school. Each student has 30 minutes to present and defend a topic.
So I created a teachers' file and 1 activity file. Here, there is 1 activity per student. Each student therefore has his or her 30-minute activity (his or her oral examination session) which is followed by 2 teachers.
In order to ease the travel of teachers, I would like teachers to stay as much as possible in the same room and their schedules to be as contiguous as possible.
Is it possible to add such constraints (i.e. leave the teacher in the same room and make sure that the teacher's sessions are contiguous)
Per advance, thanks very much for your help
Kind Regards
Hello, forstera, and welcome to the forum!
In the official FET, each activity has an exact specified subject, students set (or more), and teacher (or more). If you know the exact 2 teachers for the student having the exam (activity), you can apply the official FET easily.
If you need the program (FET) to choose the 2 teachers for each student, we need to think of tricks or customize FET for your situation. It might works also in this case.
For your 2 "as much" requests: as much as possible in the same room and their schedules as contiguous as possible, I think we need to use a progressive approach, strengthening these constraints until the timetable is not possible anymore (begin with teachers max gaps say 3 and lowering them to 2 then 1 then 0, and the same for teachers same room - I think we need to define a room in a single building and use building changes constraints).
So please let me know if the program needs to choose the teachers for the student (difficult case) or they are chosen by you (easy case). Maybe you have some examples as pdf to show us (or me personally, by email, if they are private).
Hello Liviu and thanks for a so quick answer ! :)
I already know the 2 teachers ; this is given. In fact, there are a mentor and 1 or 2 experts (95% of the time, juste 1 expert).
All exam rooms are configured to accommodate certain themes and each theme can only be located in one building.
So I'll try the approach you propose :)
Thanks very much
For the max gaps per day for a teacher, do have I to define that for each teacher or is it possible to define this as a 'general constraint' ?
Thank you :)
:)
So it is the easy case, and I am sure FET should work.
Max gaps: this constraint is available for a day or for the week (you can use both). They are available for individual teachers or for all. But if you want for instance max 3 for every teacher with the exception of one who is allowed 4, you still need to add for every teacher (there are no exceptions in the general constraint, and the strongest constraint wins).
About room changes: you could add each room in a separate building and use building changes, as I said. But if you also want to use real buildings (?), this is no longer possible. In this case we need to customize and add teacher(s) max room changes per day/week (which is not available).
I will leave now and be back to answer again after some hours.
Dear Liviu,
Thanks very much for your answer. To customize for the max change room per teacher, I'm interested. Can you tell me an approximate cost of this customization
Thanks :)
Hello,
I am back :)
I offered to do the customization. A benevolent donation to the FET project is always highly appreciated, if FET is useful to you.
But of course we could do it as an agreement work, if you prefer this way, and I have done this in the past for some users. I think we could talk by email for this.
Do you need teacher(s) max room changes per day/week?
Hello Liviu,
Thanks for your answer. Yes donation can be a way, too ; I already thought about that.
I'll have to talk with the direction ; for the while I'm preparing the timtable which should be ready for next friday. I dont know If you have time to add this new constraint but I not, think I can do without it for this year. ...
Then, if the direction decide to work with your great software, I can imagine having a yearly donation for the project.
Hello and thank you for the nice intention!
I hope I can do teacher(s) max room changes per day/week in one or at most two days. I will begin work now. I will let you know the progress and when the work is hopefully ready put your custom version for download.
Note: This will be made as a custom version, because I am not sure such an option is useful for the general users of FET (it might be confusing and leading to impossible timetables).
I did it (teacher(s) max room changes per day/week and teacher(s) min gaps between room changes) and it seems OK. Please get it from https://lalescu.ro/liviu/fet/download/custom/forstera/
Please let me know.
Wow !
Thanks so much Liviu, I'm going to test it ! :)
I keep you informed :)
Thanks very much again and have a nice week-end :)
You are welcome! Thank you! You too! :)
I found an important bug in the official FET when using constraints teacher(s) max span per day allowing a one day exception of max span plus one. I am preparing the official release. Until then, I updated your version: https://lalescu.ro/liviu/fet/download/custom/forstera/
If you use such a constraint, please update.
Hello Liviu,
Thanks very very much for your help ; it's really great.
In the meanwhile.. I've another question. I fixed the maximal gaps per day for all teachers (about 120) ... but of course I've an exception. Is there way to fix a higher value for a specific teacher ? Maybe fixing the general constraint for all teachers to 50% and fixing for a specific teacher the other amount (higher) with a constraint of 100%
By the way ... I talked to the direction and they agree to support you with an annual amount.
Can you send to me your references (bank account)
Thanks very much for your help
Thank you and the direction for the very kind gesture! It is very appreciated! I have listed the two possible methods of donation (by bank account and by PayPal) on the FET donations page: https://lalescu.ro/liviu/fet/donations.html
About gaps for teachers: indeed, there are no exceptions possible for the overall teachers constraint and indeed the possible weight for such constraints is only 100%. But, since you have a custom version, everything can be further customized for your version:
1) To add exceptions for the overall teachers constraint - it is possible. I should think of the best way to make this.
2) To make the weight for teachers max gaps per day possible under 100% - it is possible. It might be complicated, since I assumed in the interaction with the other constraints that the weight will always be 100%. The reason why I made the weight possible only 100% is because otherwise the users need to use values very near to 100% (like 99.75% or 99.99%), otherwise there will be many broken constraints on gaps.
So please let me know which of these two approaches you would prefer to pursuit. The easiest for me is (1), and the recommended might also be (1), but with (2) you might obtain an overall better solution if you don't know how many gaps a solution may have in (1).
Hello Liviu,
Thanks so much for the informations :)
According to the problem of gaps per teacher , thanks very much for your proposition. Fors this year, no need to make this change; I've already asked you enough!
I wish you a very nice evening :)
Best Regards
Arnaud
Hello, Arnaud,
I will be here if you decide for other needed customizations. If you don't want anymore changes for now, you could simply add a max gaps constraint for each teacher. Just enter that dialog, press Down and Enter, then Down and Enter, so on, for each teacher. It goes fast. Then modify the needed ones.
Thank you! :)
I think I will add the constraints teachers/students max room changes per day/week and min gaps between room changes to the official FET.
I added these above constraints in the official FET, to be released in the next version, if I don't observe some critical problems.