Pseudo activities

[aliponte]

Pseudo activities are often useful. But FET does not destinguish between real and pseudo activities. Both count for the number of daily hours, for the number of continuously hours, etc..

Pseudo activities would be much more powerful an instrument, if we could determine whether they are to be counted or not in sums like I mentioned above.

Suggestion 1: Activities without any students sets are not counted.

Suggestion 2: A subject can be defined as "lazy" which means activities in this subject are not counted.

Suggestion 3: An activity tag can be assigned the property not to count the underlying activities.

aliponte

[Volker Dirr]

The idea is maybe nice. i must think more about it.

But i don't like suggestion 1:
Think especialy about hugh schools. with pseudo activities that count normaly it is very easy to incearse the number of gaps of a few teachers (compare http://www.timetabling.de/manual/FET-manual.en.html#id_22 )
If that pseudo activities don't count any longer it mean you must add constraints to every single teacher. So you must enter much more data with your variant.

Suggestion 2:
that sound intresting.

Suggestion 3:
sound also intresting.

can you explain with an sample (situation) why you want that.



what about this suggestion:
each activity has a flag/setting/option "count as gab".
of course the disadvantage is that you might modify more manualy by that.
But the advantage is it is easier to implement (i think).

But can you explain with a few real samples the situation where you want to use that. we maybe get better ideas if we think about them.

[aliponte]

@volker

Your idea is very good, I think. I hope it is not too difficult and you can add these feature some time.

[Chafik Graiguer]

I think suggetion 3 is a good one
FET should have some predifined tags like Pseudo act. with predifined settings like:not counted for the number of daily hours, for the number of continuously hours, etc..
All activities with this tag will inherit tag's propreties
and user can't delete it

[Volker Dirr]

The problem of each new flag/tag is, that it will slow down the algorithm, even if you don't use it.
So all dataset that currently use a gap constraint will slow down, even if they don't use the new feature.
similar to the other constraints with "min hours" or "max hours".
this are critical changes and many changes must be done in the generation.cpp. i can't check that at the moment. so we wrote this into TODO. i want to code other things first.
i don't think it is good the add many of those flags. i think a single flag "don't count as hour" is enough and will/should affect all constraints with "gap", "min hours" and "max hours".

what about (home) rooms. if an activity has such a flag (home) rooms shouldn't be used? but in that case the name of the flag is not good.

[aliponte]

I'm happy that you think of putting this idea into your todo list.

i think a single flag "don't count as hour" is enough and will/should affect all constraints with "gap", "min hours" and "max hours"

Please consider also this flag to affect the constraints with "days". A pseudo activity should not increase the number of days (if it is the only activity of a day). A pseudo activity should be "invisible" for all countings concerning constraints, and for countings concerning statistics (teachers, students, subjects).