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FET Support (English) => Get Help => Topic started by: Jack_Pk on September 11, 2023, 11:37:05 PM

Title: 3 non-consecutive days
Post by: Jack_Pk on September 11, 2023, 11:37:05 PM
Hello everyone
I have a problem with some teachers in my school. I need them to work only 3 of 6 days per week, but it is necessary that these days are never consecutive.
For example it is ok to work Monday, Wednesday, Friday. But Monday, Wednesday, Saturday, or Tuesday, Thursday, Saturday are also valid.

Is there any command like "max consecutive working days"?
Thanks in advance for the answers!

Jack.
Title: Re: 3 non-consecutive days
Post by: Volker Dirr on September 12, 2023, 03:09:40 PM
If the teacher has got an activity that is divided into 3 subactivities, then just choose 2 of that subactivities and add a min day constraint with value 3 and weight 100%.
If the teacher doesn't have that, then select an other activity. Maybe a activity that is divided in 2 parts. In worst case just do it with 2 random activities.
Title: Re: 3 non-consecutive days
Post by: Liviu Lalescu on September 12, 2023, 03:30:54 PM
Hello, Jack,

Unfortunately, it seems not possible perfectly with the official FET.

A customization to add a new constraint type should be possible. But I can only work on this with a contract.
Title: Re: 3 non-consecutive days
Post by: Vangelis Karafillidis on September 13, 2023, 12:09:58 PM
Try the following:
1) Add a constraint "Min days per week for a teacher" = 3 for this teacher
2) Add a constraint "Max days per week for a teacher" = 3 for this teacher
3) Add a pseudo-activity (no teacher, no students group) with split = 2, duration = 1, min days = 3, weight = 100%.
4) Add a constraint "A set of activities occupies max time slots from selection". Select all the activities of this specific teacher, along with the above mentioned pseudo-activity. Select all time slots. Let's say that this teacher has n activities. Set "Max occupied" = n.
5) Generate.

Vangelis.
 
Title: Re: 3 non-consecutive days
Post by: Jack_Pk on January 07, 2024, 05:46:43 PM
Hello everyone,
I realised that I had not thanked you for the replies, and as I am not in the habit of being rude, here I am thanking you for the replies.
Anyway, I have somehow worked it out in 'probabilistic' terms, i.e. the programme produces schedules that 80% comply with my request. I have therefore gone through a lot of variations and discarded the ones that do not fit.
Thanks again and see you soon.
Jack
Title: Re: 3 non-consecutive days
Post by: Liviu Lalescu on January 07, 2024, 05:53:50 PM
Hello, @Jack_Pk ,

You are welcome! Thank you for informing us!