[Coin-discuss] modeling with GNU MathProg

[Antonio Frangioni]

> A model class seems reasonable to me.  Are you imagining that an
> OsiSolverInterface object would be contained in the model class, or
> that the model class would inherit from the OsiSolverInterface class?
>
> Also, I'd really like to hear any other opinions out there.

I think that a model class should be entirely different from OSI, for 
several
reasons:

1) it has nothing to do with algorithms, it is a description of an 
instance

2) we could use some of the nice software that already exists, like 
FLOPC++

We have already done something like that, although rudimentary. One of 
the things
that a model class may help in doing is handling changes of the model 
for those
algorithms that use complex solution methods where different parts of 
the same
instance are handled by different solvers (think of a B&C with a 
Lagrangian
relaxation inside). What we did is a system where the model is 
responsible to keep
track of its changes for the various solvers that "register" with it as 
being
interested in knowing them. So the model object is not only a 
repository of the
data, but also of the dynamic changes of the data.

												Best

												Antonio