Re: [rules-users] Planner: Hard Constraint Prevents Moves and Swaps

[jrvirtue]

Thank you for the advice.

I've downloaded 5.5.0.Beta1 and carried out the required update steps. BTW
the new selector system seems to be a giant leap forward.

First question: Given that I want to keep certain entities together, do I
still need to employ changeMoveSelector's? or should I only use pillars?

With respect to the pillarSwapMoveSelector, as in my example above, how do I
tell it I want to base the pillar on the planningVariable timeSlots? I tried
to add a valueSelector/planningVariableName but it doesn't work. I had a
look at the source code and it seems that the planningVariableName section
of the code has been commented out.

Thanks,
Jason





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Re: [rules-users] Planner: Hard Constraint Prevents Moves and Swaps

[Geoffrey De Smet]

  
  

Op 25-09-12 20:44, Jason Virtue
  schreef:

All,
  
  
  I have a problem where I need to assign tasks:
  1.) Times
  2.) Resources based on a Resource Type
  
  
  I've used the nurse rostering problem as an example and come
up with a planning entity ResourceAssignment that looks like:
  
  
  Facts:
  Task
  ResourceType
  
  
  Variables:
  Time
  Resource
  
  
  For example:
  1.) Lets say there are two resource types Type1  Type2
  2.) A pool of resources: Resource1(type1), Resource2(type1),
Resource3(type1), Resource4(type2), Resource4(type2),
Resource5(type2) ...
  3.) Task A: that requires 1 resource of type1 and one
resource of type2
  
  
  My program creates two PlanningEntities
  ResourceAssignment1
  Fact:
  Task=A
  ResourceType=1
  Variables
  Time
  Resource
  
  
  ResourceAssignment2
  Fact:
  Task=A
  ResourceType=2
  Variables:
  Time
  Resource
  
  
  I've created a rule that is designed to keep tasks starting
at the same time:
  
//tasks
  need to be in the same timeSlot
rule
  "taskInTimeSlot"
 when
 $ra1
  : ResourceAssignment ( task != null, time != null, $id : id,
  $task : task, $time : time)
 $ra2
  : ResourceAssignment ( task != null, timeSlot != null, id !=
  $id, task == $task, time != $time )
 then
 insertLogical(new
  IntConstraintOccurrence("taskInTimeSlot",
  ConstraintType.NEGATIVE_HARD,
   
  1,$ra1, $ra2));
end


*PROBLEM*

  

This
  results in:Cancelled step index (7), time spend (2848): there
  is no doable move. Terminating phase early.

  

If I
  change the constraint to a NEGATIVE_SOFT the problem is
  solved, but it doesn't scale. Any more that a few tasks and it
  doesn't seem to be able to find solutions.


What I
  need is for swaps and moves to change the time on multiple
  ResourceAssignments together.
  

Take a look at pillarSwapMove.

You might want to upgrade to 5.5.0.Beta1 (follow the upgrade script)
and take advantage of the improved pillarSwapMove there,
as well as the documentation that now explains it.

  

  

Am I
  going about the problem the right way? Do I need something
  other than the generic move/swap factories?
  

A custom MoveListFactory gives you full control, so that will give
you even more flexiblity, at the cost of more implementation work.

  

  

Thanks
  in advance,
Jason
  
  
  
  
  
  
  
  
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[rules-users] Planner: Hard Constraint Prevents Moves and Swaps

[Jason Virtue]

All,

I have a problem where I need to assign tasks:
1.) Times
2.) Resources based on a Resource Type

I've used the nurse rostering problem as an example and come up with a
planning entity ResourceAssignment that looks like:

Facts:
Task
ResourceType

Variables:
Time
Resource

For example:
1.) Lets say there are two resource types Type1  Type2
2.) A pool of resources: Resource1(type1), Resource2(type1),
Resource3(type1), Resource4(type2), Resource4(type2), Resource5(type2) ...
3.) Task A: that requires 1 resource of type1 and one resource of type2

My program creates two PlanningEntities
ResourceAssignment1
Fact:
Task=A
ResourceType=1
Variables
Time
Resource

ResourceAssignment2
Fact:
Task=A
ResourceType=2
Variables:
Time
Resource

I've created a rule that is designed to keep tasks starting at the same
time:

//tasks need to be in the same timeSlot

rule taskInTimeSlot

when

$ra1 : ResourceAssignment ( task != null, time != null, $id : id, $task :
task, $time : time)

$ra2 : ResourceAssignment ( task != null, timeSlot != null, id != $id, task
== $task, time != $time )

then

insertLogical(new IntConstraintOccurrence(taskInTimeSlot,
ConstraintType.NEGATIVE_HARD,

1,$ra1, $ra2));

end


*PROBLEM*


This results in: Cancelled step index (7), time spend (2848): there is no
doable move. Terminating phase early.


If I change the constraint to a NEGATIVE_SOFT the problem is solved, but it
doesn't scale. Any more that a few tasks and it doesn't seem to be able to
find solutions.


What I need is for swaps and moves to change the time on multiple
ResourceAssignments together.


Am I going about the problem the right way? Do I need something other than
the generic move/swap factories?


Thanks in advance,

Jason
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