[Osi] milp support in OSI

[Matthew Saltzman]

On Thu, 2009-04-23 at 12:42 -0400, Kipp Martin wrote:
> Hi Laci and Matt:
> 
> > 
> > OK In a broad sense, though, the idea of having a generic API for MILPs
> > is a worthy one.  Conceptually, the C++ class we currently call
> > OsiSoverInterface and its descendents are distinct from the idea of a
> > generic solver API, which may consist of different classes realizing
> > different pieces of it.
> 
> Actually the OSInstance class is a very generic solver API for not just 
> MILPs but for nonlinear problems. We have also just completed our 
> OSOption interface which is an API for solver options and are finishing 
> up the OSResult API for solution results.

I've often thought that the OS spec would be a good starting point for
this discussion.   I need to look into it some more, though.

> 
> Cheers
> > 
> >> --Laci
> >>
> >> On Thu, 23 Apr 2009, Matthew Galati wrote:
> >>
> >>> Currently OSI does support the branchAndBound function to solve a MILP.
> >>> However, I don't see any access methods for MILP statistics afterwards (or
> >>> any other MILP-type manipulation methods). Is there any intention to add
> >>> this? For example, how do I get the number of nodes used, the gap, how do I
> >>> set options specific to MILP for say, Cplex or Xpress calls?
> >>>
> >>> I can always cast an Osi to an OsiCpx and then get CpxLp and CpxEnv ptrs and
> >>> then use Cpx directly -- but obviously all of this defeats the purpose of
> >>> having OSI.
> >>>
> >>> Thanks,
> >>> Matt
> >>>
> >> _______________________________________________
> >> Osi mailing list
> >> Osi at list.coin-or.org
> >> http://list.coin-or.org/mailman/listinfo/osi
> 
> 
-- 
                Matthew Saltzman

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