A much more impressive effect of dual "textbook" ratio test vs dual long step (us04 is a test lp instance from http://www.sztaki.hu/~meszaros/public_ftp/lptestset/ ):
GLPSOL: GLPK LP/MIP Solver, v4.60 Parameter(s) specified in the command line: us04.mps --dual --log 1.log Reading problem data from 'us04.mps'... Problem: us04.mps Objective: 164 164 rows, 28016 columns, 325554 non-zeros 197828 records were read Free objective row was removed GLPK Simplex Optimizer, v4.60 163 rows, 28016 columns, 297538 non-zeros Preprocessing... 163 rows, 28016 columns, 297538 non-zeros Scaling... A: min|aij| = 1.000e+00 max|aij| = 1.000e+00 ratio = 1.000e+00 Problem data seem to be well scaled Constructing initial basis... Size of triangular part is 107 # 0: obj = -2.603575500e+07 inf = 0.000e+00 (124) # 500: obj = -2.510505500e+07 inf = 0.000e+00 (121) # 1000: obj = -2.415973800e+07 inf = 0.000e+00 (121) # 1500: obj = -2.290869854e+07 inf = 0.000e+00 (121) # 2000: obj = -2.166928031e+07 inf = 0.000e+00 (121) # 2500: obj = -2.107302139e+07 inf = 0.000e+00 (121) # 3000: obj = -2.037209973e+07 inf = 0.000e+00 (121) # 3500: obj = -1.911491575e+07 inf = 0.000e+00 (121) # 4000: obj = -1.813316013e+07 inf = 0.000e+00 (116) # 4500: obj = -1.732948957e+07 inf = 0.000e+00 (123) # 5000: obj = -1.653905458e+07 inf = 0.000e+00 (126) # 5500: obj = -1.580929007e+07 inf = 0.000e+00 (131) # 6000: obj = -1.521174582e+07 inf = 0.000e+00 (122) # 6500: obj = -1.461142784e+07 inf = 0.000e+00 (117) 1 # 7000: obj = -1.412392051e+07 inf = 0.000e+00 (117) # 7500: obj = -1.345972953e+07 inf = 0.000e+00 (117) # 8000: obj = -1.286223035e+07 inf = 0.000e+00 (117) # 8500: obj = -1.242879305e+07 inf = 0.000e+00 (117) # 9000: obj = -1.204674328e+07 inf = 0.000e+00 (117) # 9500: obj = -1.157789201e+07 inf = 0.000e+00 (117) # 10000: obj = -1.111477017e+07 inf = 0.000e+00 (117) # 10500: obj = -1.070569503e+07 inf = 0.000e+00 (118) # 11000: obj = -1.033423980e+07 inf = 0.000e+00 (118) # 11500: obj = -1.004850164e+07 inf = 0.000e+00 (130) # 12000: obj = -9.759715506e+06 inf = 0.000e+00 (124) # 12500: obj = -9.511245138e+06 inf = 0.000e+00 (133) # 13000: obj = -9.306469991e+06 inf = 0.000e+00 (130) # 13500: obj = -9.123506862e+06 inf = 0.000e+00 (137) # 14000: obj = -8.971916713e+06 inf = 0.000e+00 (137) # 14500: obj = -8.795486836e+06 inf = 0.000e+00 (138) # 15000: obj = -8.625822164e+06 inf = 0.000e+00 (138) # 15500: obj = -8.464863209e+06 inf = 0.000e+00 (143) # 16000: obj = -8.314036226e+06 inf = 0.000e+00 (143) # 16500: obj = -8.104283361e+06 inf = 0.000e+00 (143) # 17000: obj = -7.903658168e+06 inf = 0.000e+00 (143) # 17500: obj = -7.691391088e+06 inf = 0.000e+00 (117) 1 # 18000: obj = -7.471289102e+06 inf = 0.000e+00 (117) # 18500: obj = -7.251299685e+06 inf = 0.000e+00 (117) # 19000: obj = -7.041476624e+06 inf = 0.000e+00 (117) # 19500: obj = -6.816133060e+06 inf = 0.000e+00 (117) # 20000: obj = -6.612029779e+06 inf = 0.000e+00 (117) # 20500: obj = -6.421751911e+06 inf = 0.000e+00 (117) # 21000: obj = -6.218943173e+06 inf = 0.000e+00 (117) # 21500: obj = -6.015310557e+06 inf = 0.000e+00 (119) # 22000: obj = -5.841747391e+06 inf = 0.000e+00 (120) # 22500: obj = -5.640444478e+06 inf = 0.000e+00 (144) # 23000: obj = -5.460614012e+06 inf = 0.000e+00 (141) # 23500: obj = -5.316754756e+06 inf = 0.000e+00 (145) # 24000: obj = -5.218218414e+06 inf = 0.000e+00 (144) # 24500: obj = -5.164995476e+06 inf = 0.000e+00 (145) # 25000: obj = -5.121545248e+06 inf = 0.000e+00 (114) 1 # 25500: obj = -5.064826380e+06 inf = 0.000e+00 (114) # 26000: obj = -5.019705857e+06 inf = 0.000e+00 (114) # 26500: obj = -4.873401450e+06 inf = 0.000e+00 (114) # 27000: obj = -4.741044773e+06 inf = 0.000e+00 (114) # 27500: obj = -4.579456204e+06 inf = 0.000e+00 (114) # 28000: obj = -4.441922239e+06 inf = 0.000e+00 (114) # 28500: obj = -4.346852346e+06 inf = 0.000e+00 (114) # 29000: obj = -4.265109421e+06 inf = 0.000e+00 (114) # 29500: obj = -4.188916175e+06 inf = 0.000e+00 (114) # 30000: obj = -4.126386369e+06 inf = 0.000e+00 (113) # 30500: obj = -4.076516368e+06 inf = 0.000e+00 (114) # 31000: obj = -4.046542121e+06 inf = 0.000e+00 (114) # 31500: obj = -3.966998373e+06 inf = 0.000e+00 (115) # 32000: obj = -3.816651283e+06 inf = 0.000e+00 (117) # 32500: obj = -3.644031999e+06 inf = 0.000e+00 (114) 1 # 33000: obj = -3.487010699e+06 inf = 0.000e+00 (114) # 33500: obj = -3.339101604e+06 inf = 0.000e+00 (114) # 34000: obj = -3.209108153e+06 inf = 0.000e+00 (114) # 34500: obj = -3.114047893e+06 inf = 0.000e+00 (119) # 35000: obj = -3.039669616e+06 inf = 0.000e+00 (125) # 35500: obj = -2.908678108e+06 inf = 0.000e+00 (125) # 36000: obj = -2.796670247e+06 inf = 0.000e+00 (133) # 36500: obj = -2.703582699e+06 inf = 0.000e+00 (134) # 37000: obj = -2.637234445e+06 inf = 0.000e+00 (135) # 37500: obj = -2.548846816e+06 inf = 0.000e+00 (139) # 38000: obj = -2.463545534e+06 inf = 0.000e+00 (142) # 38500: obj = -2.381415127e+06 inf = 0.000e+00 (141) # 39000: obj = -2.315608246e+06 inf = 0.000e+00 (140) # 39500: obj = -2.269581994e+06 inf = 0.000e+00 (144) # 40000: obj = -2.239871977e+06 inf = 0.000e+00 (133) # 40500: obj = -2.209604958e+06 inf = 0.000e+00 (143) # 41000: obj = -2.165105509e+06 inf = 0.000e+00 (114) 1 # 41500: obj = -2.065117751e+06 inf = 0.000e+00 (114) # 42000: obj = -1.988336995e+06 inf = 0.000e+00 (113) # 42500: obj = -1.915683025e+06 inf = 0.000e+00 (113) # 43000: obj = -1.855272824e+06 inf = 0.000e+00 (113) # 43500: obj = -1.827452739e+06 inf = 0.000e+00 (113) # 44000: obj = -1.778495041e+06 inf = 0.000e+00 (113) # 44500: obj = -1.722063128e+06 inf = 0.000e+00 (111) # 45000: obj = -1.681863362e+06 inf = 0.000e+00 (119) # 45500: obj = -1.656471114e+06 inf = 0.000e+00 (120) # 46000: obj = -1.634488637e+06 inf = 0.000e+00 (134) # 46500: obj = -1.590344052e+06 inf = 0.000e+00 (114) 1 # 47000: obj = -1.558818037e+06 inf = 0.000e+00 (114) # 47500: obj = -1.543609425e+06 inf = 0.000e+00 (114) # 48000: obj = -1.517397972e+06 inf = 0.000e+00 (113) # 48500: obj = -1.472417150e+06 inf = 0.000e+00 (112) # 49000: obj = -1.440310148e+06 inf = 0.000e+00 (113) # 49500: obj = -1.426485913e+06 inf = 0.000e+00 (112) # 50000: obj = -1.358869516e+06 inf = 0.000e+00 (129) # 50500: obj = -1.279290469e+06 inf = 0.000e+00 (124) # 51000: obj = -1.216084254e+06 inf = 0.000e+00 (128) # 51500: obj = -1.166456043e+06 inf = 0.000e+00 (131) # 52000: obj = -1.137577352e+06 inf = 0.000e+00 (132) # 52500: obj = -1.124247452e+06 inf = 0.000e+00 (132) # 53000: obj = -1.090594754e+06 inf = 0.000e+00 (111) 1 # 53500: obj = -1.056498198e+06 inf = 0.000e+00 (111) # 54000: obj = -1.035740051e+06 inf = 0.000e+00 (110) # 54500: obj = -9.935224851e+05 inf = 0.000e+00 (111) # 55000: obj = -9.759412499e+05 inf = 0.000e+00 (111) # 55500: obj = -9.352088913e+05 inf = 0.000e+00 (111) # 56000: obj = -9.134047204e+05 inf = 0.000e+00 (114) # 56500: obj = -8.966518456e+05 inf = 0.000e+00 (114) # 57000: obj = -8.518567116e+05 inf = 0.000e+00 (113) 1 # 57500: obj = -8.218172354e+05 inf = 0.000e+00 (113) # 58000: obj = -8.094484394e+05 inf = 0.000e+00 (113) # 58500: obj = -7.855532946e+05 inf = 0.000e+00 (113) # 59000: obj = -7.335774382e+05 inf = 0.000e+00 (112) # 59500: obj = -6.964221848e+05 inf = 0.000e+00 (110) # 60000: obj = -6.634387229e+05 inf = 0.000e+00 (110) # 60500: obj = -6.151954989e+05 inf = 0.000e+00 (142) # 61000: obj = -5.951245895e+05 inf = 0.000e+00 (141) # 61500: obj = -5.745881074e+05 inf = 0.000e+00 (111) 1 # 62000: obj = -5.271600240e+05 inf = 0.000e+00 (111) # 62500: obj = -4.967302732e+05 inf = 0.000e+00 (111) # 63000: obj = -4.824083888e+05 inf = 0.000e+00 (110) # 63500: obj = -4.618944228e+05 inf = 0.000e+00 (110) # 64000: obj = -4.236553285e+05 inf = 0.000e+00 (111) 1 # 64500: obj = -3.982556592e+05 inf = 0.000e+00 (111) # 65000: obj = -3.763865564e+05 inf = 0.000e+00 (111) # 65500: obj = -3.504476599e+05 inf = 0.000e+00 (112) # 66000: obj = -3.296727263e+05 inf = 0.000e+00 (112) # 66500: obj = -3.137806456e+05 inf = 0.000e+00 (112) 1 # 67000: obj = -2.794097187e+05 inf = 0.000e+00 (112) # 67500: obj = -2.540970105e+05 inf = 0.000e+00 (110) # 68000: obj = -2.395460000e+05 inf = 0.000e+00 (112) 1 # 68500: obj = -2.214512631e+05 inf = 0.000e+00 (110) # 69000: obj = -2.043903009e+05 inf = 0.000e+00 (111) # 69500: obj = -1.871851638e+05 inf = 0.000e+00 (111) # 70000: obj = -1.604190000e+05 inf = 0.000e+00 (112) 1 # 70500: obj = -1.454022702e+05 inf = 0.000e+00 (112) # 71000: obj = -1.180823333e+05 inf = 0.000e+00 (109) # 71500: obj = -9.454225412e+04 inf = 0.000e+00 (109) 1 # 72000: obj = -7.397737879e+04 inf = 0.000e+00 (107) 1 # 72500: obj = -5.517483333e+04 inf = 0.000e+00 (105) # 73000: obj = -2.917524999e+04 inf = 0.000e+00 (103) 1 # 73500: obj = -1.633183333e+04 inf = 0.000e+00 (103) 1 # 74000: obj = 3.502666671e+02 inf = 0.000e+00 (96) 1 # 74500: obj = 1.280450000e+04 inf = 0.000e+00 (72) 3 # 74806: obj = 1.773166667e+04 inf = 1.273e-11 (0) 2 OPTIMAL LP SOLUTION FOUND Time used: 883.1 secs Memory used: 37.0 Mb (38779540 bytes) GLPSOL: GLPK LP/MIP Solver, v4.60 Parameter(s) specified in the command line: us04.mps --flip --log 2.log Reading problem data from 'us04.mps'... Problem: us04.mps Objective: 164 164 rows, 28016 columns, 325554 non-zeros 197828 records were read Free objective row was removed GLPK Simplex Optimizer, v4.60 163 rows, 28016 columns, 297538 non-zeros Preprocessing... 163 rows, 28016 columns, 297538 non-zeros Scaling... A: min|aij| = 1.000e+00 max|aij| = 1.000e+00 ratio = 1.000e+00 Problem data seem to be well scaled Constructing initial basis... Size of triangular part is 107 # 0: obj = -2.603575500e+07 inf = 0.000e+00 (124) 0,0 # 421: obj = 1.773166667e+04 inf = 1.705e-12 (0) 3 10,411 OPTIMAL LP SOLUTION FOUND Time used: 2.5 secs Memory used: 37.0 Mb (38779540 bytes) _______________________________________________ Help-glpk mailing list [email protected] https://lists.gnu.org/mailman/listinfo/help-glpk
