[Coin-discuss] Time limit on presolve?

[El Dono]

Hello everybody,
    I'm trying to use the Osi interface but I have problems with some models. I load the model and the data from a mps file and I call the branchAndBound() method of my GlpkSolverInterface, but I get as output a message like "primal infisible". So I've tried loading the same mps file directly from glpsolve and there I get the correct solution. I've tried to recreate the mps file using the same model but different data (I have a mod file and various dat files and convert them into mps files when I need it). This time both glpsolve and the Osi Interface gave me the same result. So I thought the problem could be in the number of variables / constraints and did some experiments but I discovered that this is not the problem: sometimes a dat file with over 700 variables has been solved in milliseconds while smaller problems produced the "primal infeasible" messagge (obviously I'm sure they are feasible...). So I think the problem is that somehow there is a limit on the complexity of the model or on the computational time to get the solution but I can't figure out what's this limit and how to change it.
Could somebody explain me what's the matter? what am I doing wrong?
Thanks in advance,
Domenico S.

P.S.: sorry for my english, if I made some mispellings...
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