> I have these two files that i attached > > because when i fix these two files with GLPSOL, it used too long (even > days) using the commands - math - cuts, and I wanted to know if there > are ways of presolving to speed the resolution
Your mip has no feasible solution (see glpsol output below), so probably you run some other instance, not that one you posted to the list. Please note that even if your instance were feasible, I don't think that glpsol could solve it for a reasonable time because of its very large size. (prob.glp was generated from your model with the --wglp option) GLPSOL: GLPK LP/MIP Solver, v4.48 Parameter(s) specified in the command line: --glp prob.glp --log log.txt Reading problem data from `prob.glp'... Problem: file25 Objective: z 43151 rows, 18000 columns, 4604913 non-zeros 18000 integer variables, all of which are binary 4687124 lines were read GLPK Integer Optimizer, v4.48 43151 rows, 18000 columns, 4604913 non-zeros 18000 integer variables, all of which are binary Preprocessing... PROBLEM HAS NO PRIMAL FEASIBLE SOLUTION Time used: 299.5 secs Memory used: 293.9 Mb (308126836 bytes) GLPSOL: GLPK LP/MIP Solver, v4.48 Parameter(s) specified in the command line: --nomip --glp prob.glp --log log.txt Reading problem data from `prob.glp'... Problem: file25 Objective: z 43151 rows, 18000 columns, 4604913 non-zeros 18000 integer variables, all of which are binary 4687124 lines were read GLPK Simplex Optimizer, v4.48 43151 rows, 18000 columns, 4604913 non-zeros Preprocessing... PROBLEM HAS NO PRIMAL FEASIBLE SOLUTION Time used: 57.7 secs Memory used: 311.1 Mb (326187268 bytes) GLPSOL: GLPK LP/MIP Solver, v4.48 Parameter(s) specified in the command line: --nomip --nopresol --glp prob.glp --log log.txt Reading problem data from `prob.glp'... Problem: file25 Objective: z 43151 rows, 18000 columns, 4604913 non-zeros 18000 integer variables, all of which are binary 4687124 lines were read Scaling... A: min|aij| = 2.000e-02 max|aij| = 9.600e+03 ratio = 4.800e+05 GM: min|aij| = 2.207e-01 max|aij| = 4.531e+00 ratio = 2.053e+01 EQ: min|aij| = 4.886e-02 max|aij| = 1.000e+00 ratio = 2.047e+01 Constructing initial basis... Size of triangular part = 36851 GLPK Simplex Optimizer, v4.48 43151 rows, 18000 columns, 4604913 non-zeros 0: obj = 9.000000000e+03 infeas = 7.099e+02 (6300) 500: obj = 9.000000000e+03 infeas = 2.339e+02 (6300) 1000: obj = 9.000000000e+03 infeas = 5.366e+01 (6300) 1327: obj = 9.000000000e+03 infeas = 5.985e+00 (6300) PROBLEM HAS NO FEASIBLE SOLUTION Time used: 118.6 secs Memory used: 345.1 Mb (361818021 bytes) _______________________________________________ Help-glpk mailing list Help-glpk@gnu.org https://lists.gnu.org/mailman/listinfo/help-glpk