Originally posted by: SystemAdmin

Hi everybody,

When one tries to write a customized neighborhood as far as I could understand it has to be done using IloNHoodI.
Almost every thing is done in define(). Now the problem is the following:

Assume I have a representation of my current solution as a,b,c,pivot,d,e. if neighbors are defined to be swapping every two elements either of which from left side of pivot and the other one on the right hand side then depending on where pivot is I have different neighborhood seizes for every current solution.
As an example the cardinalities of sets of neighbors of a,b,c,pivot,d,e and a,b,c,d,pivot,e with respect to the swap move I mentioned are not the same.
On the other hand, another function of a derived class from IloNHoodI is

getSize()

which must know in advance how many time

define()

must be called. That means it must know what is the size of my neighborhood.
Now, I am in trouble that I do not have a unique size.

Is there any workaround for this?

Any comment is appreciated.
#CPOptimizer
#DecisionOptimization

Originally posted by: rdumeur

Dear ShGe,

The start method:

virtual 

void start(IloSolver solver, IloSolution currentSolution) = 0;

defined in IloNHoodI can be overloaded. This way you can capture the current solution and locate the pivot in the solution.
Your implementation of getSize(IloSolver) can then use this information in order to produce the correct neighborhood size.
I hope it helps.

Cheers,

Renaud
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#DecisionOptimization