Originally posted by: Zhouwei

Is it possible to implement callbacks using OPL API or from ILOG Script?

I am aware that it can be done with CPLEX API but am not sure how to do it when the original model is in OPL and is being called from C++,C#, etc. If, it is possible then how can we use abort method to terminate cplex solve process based on user input?

Thanks!
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Originally posted by: SystemAdmin

Yes, it is possible.
You can use the IloCplex object as if the model was posted using Concert APIs.

For an example how to create OPL and CPLEX objects, see http://publib.boulder.ibm.com/infocenter/oplinfoc/v6r3/topic/ilog.odms.ide.help/Content/Optimization/Documentation/OPL_Studio/_pubskel/globals/eclipse_and_xplatform/ps_opl1264.html.

Tschau,
Frank
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Originally posted by: ubrannlund

I have a solution to this in a separate thread (Aborter missing in oplall) posted today . However, I believe it is a bit unsatisfactory and would appreciate comments to it.

/Ulf
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Originally posted by: Zhouwei

What I did was: I added 'Abort()' in the callback. This stops the execution of the CPLEX.
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Originally posted by: ubrannlund

That is ok. I used to have that solution too. However, my problem was that I solved both LPs and MIPs in the same OPL model. I wanted to use "Dynamic search" for the MIPs. This means I was restricted to use only MIPInfoCallbacks. The other callbacks are incompatible with "Dynamic Search". However, the MIPInfoCallback is never called for the LPs. Therefore, if I wanted to be able to stop in the middle of an LP, I needed the abort function.

/Ulf
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Originally posted by: GuangFeng

Have you tried to use ContinuousCallback for LPs?
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Originally posted by: ubrannlund

Yes. Also continuous callback is not compatible with dynamic search.
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Originally posted by: GuangFeng

Maybe you can check Cplex.isMIP property before "using" the callbacks. If isMIP is true, you only MIPInfoCallbacks. If isMIP is false, you use ContinuousCallbacks.
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