[Coin-lpsolver] determining infeasibility in ClpInterior

[Kish Shen]

Hi,

I have been testing out ClpInterior with some test cases, and for the following simple problem:

objective: min(X)

subject to:

X + Y >= 3
X + Y <= 2
X - Y  =   0

which is obviously infeasible, and when I solve the problem with Clp's Simplex, this is indeed
what I get. However, when I solve the problem with ClpInterior, I get a solution (with X and 
Y = 1).

Looking at the code:

 	lpd->lp->interiormodel->setCholesky(cholesky);
	lpd->lp->interiormodel->primalDual();
	// Barrier done

	if (lpd->lp->interiormodel->isProvenOptimal())
	{
	    // Do crossover if optimal...
          .....
	}

where lpd->lp->interiormodel is a ClpInterior *, the isProvenOptimal() method returns true.
I assume it should not?

--Kish Shen