[Cbc] decide on feasible solution after (time/node) limit exceed

[John J Forrest]

Stefan,

Actions seem plausible.  feasibleSolution(0 is only meant for calling when
branchAndBound is active and so is not giving useful information.

If a solution had been found both bestSolution and solver->getColsolution
have best solution.  if not then bestSolution NULL and getColSolution
random.

I could add a secondary status to CbcModel when status is stopped, but
testing bestSolution is easy.

I attach a modified version of your driver.

John Forrest



(See attached file: cbctest2.cpp)


                                                                           
             Stefan Vigerske                                               
             <stefan at math.hu-b                                             
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                                       Re: [Cbc] decide on feasible        
             06/27/07 09:31 AM         solution after (time/node) limit    
                                       exceed                              
                                                                           
                                                                           
                                                                           
                                                                           
                                                                           
                                                                           




Hi,

please find attached a simple program and model which illustrates the
problem.

Stefan Vigerske wrote:
> Hi,
>
> when Cbc exists with an exceed of time or node limit, how do I decide
> whether a feasible solution has been found?
> For one model, I tried bool CbcModel::feasibleSolution(int &
> numberIntegerInfeasibilities, int & numberObjectInfeasibilities), but it
> report true and no infeasibilities, even though Cbc has not find a
> feasible point ("best objective 1E+50").
> Also the point that I get with CbcModel::solver()->getColSolution() is
> not integer feasible.
>
> Best,
> Stefan
>


--
Stefan Vigerske
Humboldt University Berlin, Numerical Mathematics
http://www.math.hu-berlin.de/~stefan
[attachment "cbctest.cpp.gz" deleted by John J Forrest/Watson/IBM]
[attachment "fixed.mps.gz" deleted by John J Forrest/Watson/IBM]
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