> I am getting back to this subject because I am facing a small > problem using GLPK both on Windows and Linux. > As I said in my previous e-mail, I managed to compile the library > to use GLPK in java for Linux, and it works fine. However, I get a > difference when running an instance under Windows on the one hand and > on Linux on the other hand: it is the same optimal solution (same > primal values for variables), but the basis is different, as well as > the dual values of constraints and variables. It is a problem as I > need to use these dual values in a Branch-and-Price algorithm to get > new columns.
> During my investigation, I saw a difference that might be linked to > this behaviour: when printing the solution into a file (using > glp_print_sol), the Karush-Kuhn-Tucker optimality conditions (at the > end) don #39;t provide exactly the same display. On the one hand > (Linux), there are 2 digits for the powers of 10 (ex: 0.00e+00), and > on the other hand (Windows), there are 3 (ex: 0.00e+000). > Could the problem I am facing be linked to a rounding problem? If > so, how can I make the result identical for Windows and Linux? > If you need the model for which this problem occurs, feel free to ask. Please see: http://list.coin-or.org/pipermail/coin-discuss/2009-March/003548.html _______________________________________________ Help-glpk mailing list [email protected] http://lists.gnu.org/mailman/listinfo/help-glpk
