[BCP] Primal and dual solution are not the same

[Sepehr Nemati Proon]

Which solver are you using?

Sepehr NP


On Fri, Aug 10, 2012 at 7:24 AM, Andrea Trautsamwieser <
andrea.trautsamwieser at boku.ac.at> wrote:

>  Hi,
>
> I want to use the dual variables for improving my algorithm, However, I
> found out that the dual solution does not equal the primal solution in each
> node, although it should.
>
> The termcode of the BCP_lp_result is 2, so it should be solved to
> optimality. I have tried to solve small test instances to check the error,
> however I have not find out what is going wrong exactly.
>
> The primal solution contains some of the new generated variables, but not
> all of the dual variables are adapted accordingly. It seems that the dual
> neglects at least one of the new algorithmic variables and so I obtain
> different objective values and the algorithmic variable is generated again
> in the next column generation iteration.
>
> Has anyone any idea to that problem?
>
> Thank you very much,
>
> Andrea
>
>
> _______________________________________________
> BCP mailing list
> BCP at list.coin-or.org
> http://list.coin-or.org/mailman/listinfo/bcp
>
>


-- 
Sepehr Nemati
PhD Student
Department of Industrial Engineering
University of Pittsburgh
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://list.coin-or.org/pipermail/bcp/attachments/20120811/b3a78ec9/attachment.html>