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<DIV><FONT face=Arial size=2>Hello everybody,</FONT></DIV>
<DIV><FONT face=Arial size=2> 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.</FONT></DIV>
<DIV><FONT face=Arial size=2>Could somebody explain me what's the matter? what
am I doing wrong?</FONT></DIV>
<DIV><FONT face=Arial size=2>Thanks in advance,</FONT></DIV>
<DIV><FONT face=Arial size=2>Domenico S.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>P.S.: sorry for my english, if I made some
mispellings...</FONT></DIV></BODY></HTML>