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FET Support (English) => Get Help => Topic started by: Peter Johnson on May 22, 2020, 12:20:42 PM

Title: Preferred rooms vs Home rooms
Post by: Peter Johnson on May 22, 2020, 12:20:42 PM
Hi,
When I was using an old version of FET, I could have a "student home room", "teacher home room" and for those activities that its teacher and student has "home room" constraint, I could define an "activity preferred room'. In this way, FET was ignoring the student and teacher's home room constraints and just consider the "activity preferred room". But now that I have switched to the new version, it says "Cannot generate timetable, because for activity with id==1 you have no allowed home room (from constraints students set home room(s) and teacher home room(s))".

What I need is that a teacher T1 has many classes, and they should be in his home room by default. The same holds for a student set S1, but the teacher T1 has just one specific class with S1, and it can be in another room (maybe in T1's home room, or S1's home room or any other room). Is there any solution to use the new version of FET and apply this, or I have to use the old version?

Thanks in advance
Title: Re: Preferred rooms vs Home rooms
Post by: Liviu Lalescu on May 22, 2020, 12:27:17 PM
Hello,

Please send me as soon as possible your .fet file, and tell me in which FET it worked. (and I assume you tried with FET-5.44.7 and it does not work?) It is a very important bug in FET if you did not change your file.
Title: Re: Preferred rooms vs Home rooms
Post by: Liviu Lalescu on May 22, 2020, 09:05:59 PM
I assume you have problems with a file like the attached one. But I tried with FET-5.27.3, release about 5 years ago, and it behaves like the current FET-5.44.7, refusing to start the generation because of conflicting home rooms constraints.

Yes, I admit, you are right. I don't remember exactly the reasons for this behavior, but I think there was a reason. I will think about it, but for the moment I think it should remain like it is. It is risky to change old code.

Other users, what do you think?
Title: Re: Preferred rooms vs Home rooms
Post by: Benahmed Abdelkrim on May 22, 2020, 09:37:43 PM
I think that this is normal behavior, there is a conflict of rooms because of an activity linked by a space constraint (home room) to different rooms by these element (teacher, student, subject).
we must remove a constraint, either that of the teacher or that of the students to allow the generation of timetable....
leaving things as they are is better and especially safe...
Title: Re: Preferred rooms vs Home rooms
Post by: Benahmed Abdelkrim on May 22, 2020, 09:44:30 PM
this is a basic constraint that we have to
absolutely respect it, otherwise we will see timetables that do not make sense
Title: Re: Preferred rooms vs Home rooms
Post by: Liviu Lalescu on May 22, 2020, 09:47:13 PM
Benahmed, the preferred rooms take precedence over home rooms. So, if there is a 100% preferred room for A1 and A2, FET should really ignore the home rooms.
Title: Re: Preferred rooms vs Home rooms
Post by: Benahmed Abdelkrim on May 22, 2020, 09:59:59 PM
therefore a preferred room must have priority over a home room?. but there are 2 constraints which dispute the priority!, and which entered I think by mistake by the user!.
Title: Re: Preferred rooms vs Home rooms
Post by: Liviu Lalescu on May 22, 2020, 10:04:20 PM
In my file, there are two home rooms contradicting with each other, but there is a preferred rooms winning over both.
Title: Re: Preferred rooms vs Home rooms
Post by: Benahmed Abdelkrim on May 23, 2020, 06:44:07 PM
Quote from: Liviu Lalescu on May 22, 2020, 10:04:20 PM
In my file, there are two home rooms contradicting with each other, but there is a preferred rooms winning over both.
Hi!
Hmm...therefore a correction must be made to take this fact into account?
Title: Re: Preferred rooms vs Home rooms
Post by: Liviu Lalescu on May 23, 2020, 06:51:22 PM
I added this in the TODO.
Title: Re: Preferred rooms vs Home rooms
Post by: Benahmed Abdelkrim on May 23, 2020, 06:54:56 PM
thank you!
Title: Re: Preferred rooms vs Home rooms
Post by: Peter Johnson on May 26, 2020, 01:25:38 PM
Sorry for the late reply.
It turns out that it does not work for the old version too! It was my mistake, but the problem is what you said.

Many thanks for your consideration.