[Cgl] Extracting Gomory cuts

[sj10 at cs.brown.edu]

On Wed, Jan 6, 2010 at 7:58 AM, Ashutosh Mahajan <asm4 at lehigh.edu> wrote:

> On Mon, 04 Jan 2010, sj10 at cs.brown.edu wrote:
>
> >    Hey,
> >
> >    I'm trying to extract Gomory cuts out of Cgl using the following code
> -
> >
> >       OsiCuts cutlist;
> >       CglGomory * gomory = new CglGomory();
> >       //gomory->setLimit(100);
> >       gomory->generateCuts(*sym, cutlist) ;
> >
> >    where sym is the OsiSymSolverInterface.
> >
> >    Unfortunately the generateCuts method is segfaulting. The same thing
> is
> >    happening for the CglProbing cuts.
>
> you need to use OsiClpSolverInterface instead of OsiSymSolverInterface.
> Gomory
> cuts are generated from the simplex tableau obtained by an LP solver like
> Clp.
> Symphony is an MILP solver. Similarly, CglProbing work with an LP solver
> only.
>
> cheers.
> ashutosh
>
>
Thanks for the reply. Unfortunately now the loadProblem method of
OsiClpSolverInterface is segfaulting. According to the Doxygen docs, the
signature for the loadProblem method in OsiSymSolverInterface and
OsiClpSolverInterface is the same and they both accept column major
representation of the matrix.

  Do you know why this might be happening?

Thanks
Sid
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