简单的实验与更困难的模型

简单的实验与更困难的模型

让我们现在考虑一个更困难的模型,glass4.mps。再次,我们阅读模型并开始优化:

gurobi> m =读取('/ opt / gurobi910 / linux64/例子/数据/玻璃4')
从文件中读取MPS格式模型/ opt / gurobi910 / linux64/ examples/data/glass4.mps.
阅读时间= 0.00秒
Glass4:396行,322栏,1815个非安利斯
gurobi> m.optimize()
Gurobi Optimizer 9.1.0 build v9.1.0rc0 (linux64)

优化具有396行,322列和1815个非系统模型指纹的模型:0x541D0AD3变量:20连续,302整数(0二进制)系数统计:矩阵范围[1E + 00,8E + 06]目标范围[1E + 00,1E+06]界限范围[1E + 00,8E + 02] RHS范围[1E + 00,8E + 06]预定删除4行和5列预定校长时间:0.00s预定:392行,317列,1815个非系统变量类型:19连续,298整数(298二进制)发现启发式解决方案:目标3.133356E + 09根放松:目标8.000024E + 08,72迭代,0.00秒节点|当前节点|目标界限|工作解释概述|OBJ深度Intinf |现任者最畅销的差距|IT / Node Time 0 0 8.0000E + 08 0 72 3.1334E + 09 8.0000E + 08 74.5% -  0s H 0 0 2.400019E + 09 8.0000E + 08 66.7% -  0s H 0 0 2.220019E + 09 8.0000E + 0864.0% -  0 0 0 0 8.0000E + 08 0 72 2.2200E + 09 8.0000E + 08 64.0% -  0s H 0 0 2.200019E + 09 8.0000E + 08 63.6% -  0s 0 0 8.0000E + 08 0 81 2.2000E +09 8.0000E + 08 63.6% -  0 0 0 0 8 8.0000E + 08 0 77 2.2000E + 09 8.0000E + 08 63.6% -  0s 0 2 8.0000E + 08 0 77 2.2000E + 09 8.0000E + 08 63.6% -  0s H.307 609 2.066686E + 09 8.0000E + 08 61.3%5.8 0s H 1126 885 1.950016E + 09 8.0000E + 08 59.0%6.0 0s H 1317 983 1.900015E + 09 8.0000E + 08 57.9%5.6 0s H 1817 1173 1.900015E +09 8.0000E + 08 57.9%5.0 0s 0s H 2656 1796 1.900015E + 09 8.0000E + 08 57.9%4.8 0s H 8305 6287 1.900015E + 09 8.0000E + 08 57.9%3.4 0s * 10878 6870 99 1.808351E + 09 8.0000E +08 55.8% 3.3 0s *12677 7866 62 1.800016e+09 8.0000e+08 55.6% 3.3 1s *17157 10811 118 1.800015e+09 8.0000e+08 55.6% 3.2 1s H19145 11166 1.750016e+09 8.0000e+08 54.3% 3.2 1s H24736 14317 1.700015e+09 8.0000e+08 52.9% 3.2 1s H24874 14315 1.700015e+09 8.0000e+08 52.9% 3.2 1s H32097 17197 1.633347e+09 8.0665e+08 50.6% 3.2 2s H32123 16354 1.600013e+09 8.1873e+08 48.8% 3.2 3s 32158 16378 1.6000e+09 118 110 1.6000e+09 8.4564e+08 47.1% 3.2 5s H32215 15596 1.533346e+09 8.6063e+08 43.9% 3.3 6s H32284 14860 1.500013e+09 8.8136e+08 41.2% 3.4 9s 32294 14867 1.2500e+09 46 93 1.5000e+09 8.8136e+08 41.2% 3.4 10s 32446 14975 1.2500e+09 52 95 1.5000e+09 9.0001e+08 40.0% 3.5 15s Interrupt request received Cutting planes: Gomory: 8 Implied bound: 13 Projected implied bound: 1 MIR: 19 Flow cover: 17 Zero half: 1 RLT: 4 Relax-and-lift: 17 Explored 57196 nodes (301282 simplex iterations) in 19.00 seconds Thread count was 8 (of 8 available processors) Solution count 10: 1.50001e+09 1.53335e+09 1.60001e+09 ... 1.80835e+09 Solve interrupted Best objective 1.500012666667e+09, best bound 1.000006945369e+09, gap 33.3334%

很明显,这个模型比之前的模型要困难得多硬币模型。实际上是最佳解决方案1200000000年,但发现解决方案需要一段时间。在让模型运行15秒后,我们中断运行(通过击中Ctrl-C,从而产生收到中断请求消息)并考虑我们的选择。打字M.Optimize()将从中断的点恢复运行。