Originally posted by: ZoharFeldman

Hi,

I have some constraints in my model that I would like to enforce "softly", that is, only if they do not create a conflict.

A possible way that I see to implement this concept is to add indicators (IloIntVar) corresponding to the evaluation of these constraints, and add a minimization objective to the model which expression is (possibly weighted) sum of these indicators.

Does this seem like a plausible way? is there a more efficient way to declare soft constraints in the cp optimizer?

Thanks,

Zohar

Hi,

using CP;

dvar int x;

subject to
{

ct1: x<=3;
ct2: x>=5;
}

will give a conflict between ct1 and ct2.

labeled constraints are soft.

regards

Originally posted by: ZoharFeldman

Thanks for your reply, Alex.

I am using c++ concert technology. Is there an analogy to this in concert?

Zohar

Hi,

have you had a look at

http://www.ibm.com/support/knowledgecenter/SSSA5P_12.6.3/ilog.odms.ide.help/refcppopl/html/conflictrefiner.html

?

regards

Originally posted by: PhilippeLaborie

Hi Zohar,

Yes, using additional variables or expressions that indicate/measure the degree of violation of the constraints is the usual way to do it in CP Optimizer.

Note that if you are using interval variables, you can exploit the notion of "optionality" of interval variables for modeling constraint violation.

Originally posted by: ZoharFeldman

Thanks much, Philippe.