[Coin-discuss] Using Osi/Clp

[Matthew Saltzman]

Oops.  Been traveling and missed Jean-Sebastein Roy's earlier reply to
this.

Thanks, Jena-Sebastein.

On Sat, 8 Jan 2005, Matthew Saltzman wrote:

> On Thu, 6 Jan 2005, Edgardo Fuchs wrote:
>
> > Dear Coin list members,
> >
> > I wish to use Osi/Clp within a stochastic optimization model to solve a
> > long-term hydro-thermal power generation dispatch problem.
> > The model was developed using OSL, but I want to migrate it to Osi/Clp.
> >
> > >From the example "build.cpp" it is clear how to construct a model from
> > scratch and solve it. But I have not found the way to perform additional
> > operations required by the dispatch model.
>
> Yes, documentation is kind of sparse.  But if you have a reading knowledge
> of C++, you can find most of what you need looking at the OSI code itself.
> See the Doxygen docs at http://www.coin-or.org/Doxygen/Osi/index.html.
> There are also some other useful examples in the Examples directory of the
> source tree and at http://coral.ie.lehigh.edu/~coin/.
>
> > Could you please give some hints or examples on how to perform the
> > following operations using Osi/Clp?
>
> I'd suggest looking at the above locations first.  If you still have
> questions, please come back and ask them here.
>
> >
> > 1. Select primal or dual simplex algorithm
>
> Look for [get/set]HintParam() (as well as the other [get/set]*Param
> methods.
>
> > 2. Add a column to the LP matrix
> > 3. Add a row to the LP matrix
> > 4. Delete and replace a row of the LP matrix
> > 5. Replace elements of the LP matrix
>
> All the above methods are in the OsiSolverInterface class.
>
> > 6. Post solve after modifications
>
> The first solve is initialSolve().  After mods, resolve with resolve().
> Not all solvers do this more efficiently than resolving from scratch, but
> most do.
>
> > 6. Scale LP problem
>
> Hints.
>
> > 7. Save and load an optimal basis
>
> [get/set]WarmStart()
>
> > 8. Direct Osi/Clp messages
>
> See the CoinMessageHandler class.
>
> >
> > Thank you in advance.
> > Sincerely,
>
> HTH.
>
> >
> > Edgardo Fuchs
> > KAS Ingenieria
> >
> >  --
> >
> > Edgardo Fuchs
> >
> > Santiago, Chile
> >
> > Tel: +56 (2) 435 0090
> > Cel: +56 9837 8433
> >
> >
>
>

-- 
		Matthew Saltzman

Clemson University Math Sciences
mjs AT clemson DOT edu
http://www.math.clemson.edu/~mjs