It happens that if the solution you pass is incorrect (or incorrect for the current problem that, again, can differ from the original one) GLPK can return OPTIMAL INTEGER SOLUTION FOUND.
2013/8/6 Giorgio Sartor <[email protected]> > Well, I don't know what you mean exactly but setting parm.presolve = ON is > never NECESSARY! (It is necessary only if you don't want to use glp_simplex > before glp_intopt). If you don't use it, my suggestion is to use > glp_simplex before glp_intopt and disable parm.presolve. In this case, if > the integer solution found is incorrect means that the solution you pass is > incorrect. > > > 2013/8/6 Le Dinh Danh <[email protected]> > >> Hi G.S, >> It is neccesary to set parm.presolve=ON before solving MIP. In fact, I've >> tried with parm.presolve=OFF but the results are always 0. Anyway, thank >> you. >> >> >> On Mon, Aug 5, 2013 at 5:34 PM, Giorgio Sartor <[email protected]>wrote: >> >>> Ok. Just try parm.presolve=OFF and let me know if then works. >>> >>> >>> - G. S. - >>> >>> Il giorno 05/ago/2013, alle ore 16:51, Le Dinh Danh <[email protected]> >>> ha scritto: >>> >>> Hi Giorgio Sartor, >>> >>> On Mon, Aug 5, 2013 at 4:14 PM, Giorgio Sartor <[email protected]>wrote: >>> >>>> Is glp_iocp.presolve activated? >>>> >>> Yes, I have already set parm.presolve = ON. >>> >>>> A common cause of incorrect solutions is that your solution is correct >>>> for the original problem but not correct for the current problem (which >>>> could have been modified by GLPK during the solving process). >>>> Stupid question: does your solution start from position 1 of the array? >>>> >>> Yes, of course. >>> >>>> >>>> - G. S. - >>>> >>>> Il giorno 05/ago/2013, alle ore 14:58, Le Dinh Danh <[email protected]> >>>> ha scritto: >>>> >>>> With "the result is still incorrect" I mean after calling the callback >>>> function, the solver find the solution but it is not correct one. I don't >>>> know why. If I don't call the cacllback, the solve provide a good solution. >>>> I can check it manually. >>>> >>>> >>>> On Mon, Aug 5, 2013 at 1:19 PM, Giorgio Sartor <[email protected]>wrote: >>>> >>>>> What do you mean with "the result is still incorrect"? >>>>> >>>>> >>>>> - G. S. - >>>>> >>>>> Il giorno 05/ago/2013, alle ore 12:57, Le Dinh Danh <[email protected]> >>>>> ha scritto: >>>>> >>>>> > the result is still incorrect. >>>>> >>>> >>>> >>>> >>>> -- >>>> Le Dinh Danh >>>> LIRMM, 161 rue Ada, 34095 Montpellier Cedex 5 >>>> Email: [email protected]; [email protected] >>>> Tel: (+84) 912.449.666; (+33) 6.52.98.59.66 >>>> >>>> >>> >>> >>> -- >>> Le Dinh Danh >>> LIRMM, 161 rue Ada, 34095 Montpellier Cedex 5 >>> Email: [email protected]; [email protected] >>> Tel: (+84) 912.449.666; (+33) 6.52.98.59.66 >>> >>> >> >> >> -- >> Le Dinh Danh >> LIRMM, 161 rue Ada, 34095 Montpellier Cedex 5 >> Email: [email protected]; [email protected] >> Tel: (+84) 912.449.666; (+33) 6.52.98.59.66 >> >> >
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