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FET Support (English) => Get Help => Topic started by: Andrea Giordano on September 20, 2011, 04:27:13 PM

Title: Elaboration time
Post by: Andrea Giordano on September 20, 2011, 04:27:13 PM
Dear Liviu, my timetable has grown ... I entered nearly all activities and added the teacher assistant in subactivities. It takes a little too much even if it is solvable. Maybe be there is a contraint too strict that lower the speed too much.
Would you get a glance to it?
How can I improve it?
Hints accepted  :)
Thanks'
Title: Re: Elaboration time
Post by: Liviu Lalescu on September 20, 2011, 04:59:00 PM
Only 3 max gaps per week for teachers? (I see that per day is 2, so I assume 3 might be a typo).

Edited to add: also, that 95% max 7 hours per day for teachers looks ugly to me.
Title: Re: Elaboration time
Post by: Andrea Giordano on September 20, 2011, 11:45:33 PM
did it ... better result! Playing with constraint ... and trying to fix things. It is working.
Title: Re: Elaboration time
Post by: Andrea Giordano on September 21, 2011, 09:07:13 AM
Problem I have to add 2 activities IRC 6E and IRC5B of teacher V. in thursday slot 3 and I tried with constraint teacher not available (but got some error reply beacuse of the other constraint) and tryed with set of activities in a certain hour adn day ... but tacking too long.
Is there a better way?
Thanks
Title: Re: Elaboration time
Post by: Liviu Lalescu on September 21, 2011, 09:25:38 AM
A teacher cannot have two activities in the same slot.
Title: Re: Elaboration time
Post by: Andrea Giordano on September 21, 2011, 12:23:58 PM
no sorry 2 activities for 2 slots
Title: Re: Elaboration time
Post by: Liviu Lalescu on September 21, 2011, 12:28:34 PM
The best is 2 x ConstraintActivityPreferredStartingTime. Good is also ConstraintTeacherNotAvailable, but do not add these as activities to that teacher.
Title: Re: Elaboration time
Post by: Andrea Giordano on September 21, 2011, 12:41:07 PM
QuoteThe best is 2 x ConstraintActivityPreferredStartingTime. Good is also ConstraintTeacherNotAvailable, but [highlight]do not add these as activities to that teacher.[/highlight]
what do you mean?
Title: Re: Elaboration time
Post by: Liviu Lalescu on September 21, 2011, 12:44:20 PM
Quote
QuoteThe best is 2 x ConstraintActivityPreferredStartingTime. Good is also ConstraintTeacherNotAvailable, but [highlight]do not add these as activities to that teacher.[/highlight]
what do you mean?

Say teacher T has activities A1 and A2 on Monday 8:00 and Tuesday 8:00 (durations 1 each). Then you can make teacher T not available on Mon 8:00 and Tue 8:00, but in the list of activities do not add A1 and A2.
Title: Re: Elaboration time
Post by: Andrea Giordano on September 21, 2011, 01:15:54 PM
taking too long having blocked just 2 slots .... isn't it strange?

Do I have to delete activities A1 and A2???? It seems odd sorry. I don't understand.
... updated attached file!


Working with the attached file ... (raised some constraint) 
this the answer Orario n.: 1 => Tempo scaduto per l'orario corrente. Numero massimo di attività piazzate: 460 (dopo 1 h 12 m 4 s).
Orario n.: 2 => L'orario ha 4.5 conflitti leggeri ed è stato trovato in 0 ore, 14 minuti e 56 secondi.
Orario n.: 3 => Tempo scaduto per l'orario corrente. Numero massimo di attività piazzate: 459 (dopo 12 m 10 s).
Orario n.: 4 => Tempo scaduto per l'orario corrente. Numero massimo di attività piazzate: 459 (dopo 14 m 18 s).
Weird!
Title: Re: Elaboration time
Post by: Liviu Lalescu on September 23, 2011, 11:21:26 AM
Quotetaking too long having blocked just 2 slots .... isn't it strange?

Do I have to delete activities A1 and A2???? It seems odd sorry. I don't understand.
... updated attached file!


Working with the attached file ... (raised some constraint) 
this the answer Orario n.: 1 => Tempo scaduto per l'orario corrente. Numero massimo di attività piazzate: 460 (dopo 1 h 12 m 4 s).
Orario n.: 2 => L'orario ha 4.5 conflitti leggeri ed è stato trovato in 0 ore, 14 minuti e 56 secondi.
Orario n.: 3 => Tempo scaduto per l'orario corrente. Numero massimo di attività piazzate: 459 (dopo 12 m 10 s).
Orario n.: 4 => Tempo scaduto per l'orario corrente. Numero massimo di attività piazzate: 459 (dopo 14 m 18 s).
Weird!

1) Maybe the timetable is too difficult in general, or check Schileo and Fabris.

2) Yes, your results are normal. For instance Oradea-FS or CONCORDIA (these can solve in 1 minute or in 5 hours) or Timisoara-Econ (may solve in 2 hours or not solve after 24 hours).

3) Please let us know those 4.5 soft conflicts, or use them like that: those constraint are probably impossible. So, make the weight of min days constraints in that list, 0%. And maybe raise the other possible ones to 100% (Volker's technique). And do maybe similar for other constraints types.

PS: If you edit your message after a longer time (say more than 24 hours), and the edit is important, it is maybe better to post a new reply, so we know the update. I am not sure, though.