Gurobi 5.0.1 (linux64) logging started Mon Feb 4 18:52:36 2013 Optimize a model with 12383 rows, 1764 columns and 37926 nonzeros Presolve removed 1434 rows and 898 columns Presolve time: 0.09s Presolved: 10949 rows, 866 columns, 33587 nonzeros Variable types: 19 continuous, 847 integer (847 binary) Found heuristic solution: objective 41081.000000 Root relaxation: objective 3.156340e+04, 3594 iterations, 0.15 seconds Nodes | Current Node | Objective Bounds | Work Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time 0 0 31563.3988 0 8 41081.0000 31563.3988 23.2% - 0s H 0 0 31580.000000 31563.3988 0.05% - 0s H 0 0 31576.000000 31563.3988 0.04% - 0s 0 0 31564.1860 0 23 31576.0000 31564.1860 0.04% - 0s 0 0 31564.1860 0 10 31576.0000 31564.1860 0.04% - 0s H 0 0 31574.000000 31564.1860 0.03% - 0s 0 0 31565.0554 0 26 31574.0000 31565.0554 0.03% - 0s H 0 0 31572.000000 31565.0554 0.02% - 0s 0 1 31565.0730 0 26 31572.0000 31565.0730 0.02% - 0s H 1 1 31571.000000 31565.0730 0.02% 0.0 0s Cutting planes: Gomory: 4 Cover: 1 Implied bound: 1 Clique: 1 MIR: 10 Zero half: 1 Explored 18 nodes (4054 simplex iterations) in 0.47 seconds Thread count was 1 (of 16 available processors) Optimal solution found (tolerance 1.00e-04) Best objective 3.157100000000e+04, best bound 3.156800000000e+04, gap 0.0095%