Author Topic: amalgam of two constraints!  (Read 557 times)

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Benahmed Abdelkrim

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amalgam of two constraints!
« on: July 09, 2016, 02:56:26 PM »
  amalgam of two constraints
   returning to the file Orazio , and if one devotes some time, we will discover that there is a confusion between these two constraints used. to know:
1. Activities same starting time(day+hour)
2. Activities max simultaneous time slots./max simulaneous=2.
   on the first constraint, it is used to allow three activities being together in the same time slot, but only three not four, I supose independently of the Second constraint.
but the program (or algorithm), lets see four activities together, instead of three provided by the user ?!
giving the impression that fet considers these three activities that start at the same time as a single activity in order to satisfy the second constraint?
I think we need more explanation ...
I attach a file
Bests Regards
« Last Edit: July 09, 2016, 03:41:39 PM by Benahmed Abdelkrim »
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Volker Dirr

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Re: amalgam of two constraints!
« Reply #1 on: July 09, 2016, 03:52:31 PM »
it is all correct.
there are same starting time constraints with id 1, 19,37
but the max sumoulatoisly constraint contain only id 1, not 19 and also not 37.
so it is correct. if it should count 19 and 37 also, then you also need to add it into the max simoultanously constraint.

all other same strating time has the same "problem".

so the algorithm is fine. the user done a bug, because he forgot to add id 19 and 37, and ...

Benahmed Abdelkrim

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Re: amalgam of two constraints!
« Reply #2 on: July 10, 2016, 02:25:38 AM »
   Sorry mr Volker,...all activities with the constraint "same starting time" is not in the constraint "Max simultaneous…", otherwise the timetable will be impossible. as can be verified easily.
I attach the pictures:
the picture "pict_stt" shows the activities "same starting time", with the following IDs:
1   ,    19    ,    37
3   ,    21    ,    39
5   ,    23    ,    55
7   ,    25    ,    57
    the two pictures "pict_msts1" and "pict_msts2" show activities "Max simultaneous in selected time slots" without the activities listed above.
thanks for your understanding
« Last Edit: July 10, 2016, 03:55:41 AM by Benahmed Abdelkrim »
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Liviu Lalescu

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Re: amalgam of two constraints!
« Reply #3 on: July 10, 2016, 02:53:57 AM »
M. Benahmed, the constraints are satisfied. You get 4 activities in a time slot because these activities are not in the max simultaneous constraint.

FET is OK with this file.

Benahmed Abdelkrim

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Re: amalgam of two constraints!
« Reply #4 on: July 10, 2016, 03:44:26 AM »
hmm ... maybe we can find a way out through the addition of a new constraint as "min simultaneous " . what is your opinion?
B.A/krim

Volker Dirr

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Re: amalgam of two constraints!
« Reply #5 on: July 10, 2016, 03:55:17 AM »
why do you need it? can you please explain a sitiuation where that is needed.

Liviu Lalescu

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Re: amalgam of two constraints!
« Reply #6 on: July 10, 2016, 04:11:48 AM »
hmm ... maybe we can find a way out through the addition of a new constraint as "min simultaneous " . what is your opinion?

I guess it is very difficult to implement. Also, I think it is not useful for our situation.

Benahmed Abdelkrim

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Re: amalgam of two constraints!
« Reply #7 on: July 10, 2016, 11:41:22 AM »
héllo!
   here is a solution which allows for a maximum of 3 activities in each time slot. by simply adding another constraint "Max simultaneous", but select this time all activities, and giving it a value of 3.
   I am sorry for my drift, because I was very tired these days.
I attach a file
« Last Edit: July 10, 2016, 12:13:11 PM by Benahmed Abdelkrim »
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