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 Hello Daniele, *  The routine ios_relative_gap computes the relative mip gap using the *  formula: * *     gap = |best_mip - best_bnd| / (|best_mip| + DBL_EPSILON) Minimization example: - Best integer solution 2 - Best bound -1.3 => Gap = (2 - -1.3) / 2 = 1.65 If you called glpsol --mipgap 1.7 -m problem.mod the solver would stop with this soution. Beware: The mip gap may rise while you solution gets better: Integer optimization begins... +   213: mip =     not found yet <=              +inf        (1; 0) +   481: >>>>>  -4.000000000e+00 <=   7.000000000e+00 275.0% (10; 0) +   875: >>>>>  -3.000000000e+00 <=   2.600000000e+00 186.7% (15; 3) +  1215: >>>>>  -1.000000000e+00 <=   1.000000000e+00 200.0% (15; 11) +  1397: mip =  -1.000000000e+00 <=     tree is empty   0.0% (0; 47) INTEGER OPTIMAL SOLUTION FOUND The mip gap rose from 1.867 to 2. while the objective rose from -3 to -1 in this maximization problem. Best regards Xypron On 30.07.2012 16:22, Daniele Micarelli wrote: hi I wanted to know more precisely what is the command: mipgap tol and the number that goes in place of tol to indicate precisely what is? thank you very much ```_______________________________________________ Help-glpk mailing list address@hidden https://lists.gnu.org/mailman/listinfo/help-glpk ```