<div dir="ltr"><div><font color="#000000" face="arial, sans-serif">(attaching large mps files is not allowed, so I'm resending)</font></div><div><font color="#000000" face="arial, sans-serif"><br></font></div><span style="color:rgb(0,0,0);font-family:arial,sans-serif;font-size:13px">I am calling libCbcSolver as follows ( cbc 2.8 windows 7 64 bit)</span><div style="color:rgb(0,0,0);font-family:arial,sans-serif;font-size:13px">
<br></div><blockquote style="color:rgb(0,0,0);font-family:arial,sans-serif;font-size:13px;margin:0px 0px 0px 40px;border:none;padding:0px"><div> CbcModel cbc(osi);</div><div> CbcMain0(cbc);</div><div> cbc.setDblParam(CbcModel::CbcMaximumSeconds, 1800);</div>
<div> const char *argv2[] = {"schedulemip", "-preprocess", "off", "-solve", "-quit"};</div><div> CbcMain1(5, argv2, cbc); </div></blockquote><div style="color:rgb(0,0,0);font-family:arial,sans-serif;font-size:13px">
<br></div><div style="color:rgb(0,0,0);font-family:arial,sans-serif;font-size:13px">and the tail end of the output looks like</div><div style="color:rgb(0,0,0);font-family:arial,sans-serif;font-size:13px">---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------</div>
<blockquote style="color:rgb(0,0,0);font-family:arial,sans-serif;font-size:13px;margin:0px 0px 0px 40px;border:none;padding:0px"><div>Cbc0010I After 10800 nodes, 1166 on tree, 169460.67 best solution, best possible 157572.58 (804.68 seconds)</div>
<div>Cbc0010I After 10900 nodes, 1214 on tree, 169460.67 best solution, best possible 157572.58 (810.69 seconds)</div><div>Cbc0010I After 11000 nodes, 1264 on tree, 169460.67 best solution, best possible 157572.58 (815.13 seconds)</div>
<div>Cbc0010I After 11100 nodes, 1311 on tree, 169460.67 best solution, best possible 158109.85 (835.74 seconds)</div><div>Cbc0010I After 11200 nodes, 1361 on tree, 169460.67 best solution, best possible 158345.27 (853.65 seconds)</div>
<div>Cbc0010I After 11300 nodes, 1411 on tree, 169460.67 best solution, best possible 158404.02 (869.75 seconds)</div><div>Cbc0010I After 11400 nodes, 1461 on tree, 169460.67 best solution, best possible 158464.46 (886.81 seconds)</div>
<div>Cbc0020I Exiting on maximum time</div><div>Cbc0005I Partial search - best objective 169460.67 (best possible 158464.46), took 1871577 iterations and 11482 nodes (900.43 seconds)</div><div>Cbc0032I Strong branching done 8334 times (76189 iterations), fathomed 9 nodes and fixed 1 variables</div>
<div>Cbc0035I Maximum depth 124, 223498 variables fixed on reduced cost</div><div>Cbc0038I Probing was tried 1579 times and created 82296 cuts of which 1 were active after adding rounds of cuts (11.281 seconds)</div><div>
Cbc0038I Gomory was tried 7626 times and created 8129 cuts of which 2464 were active after adding rounds of cuts (144.295 seconds)</div><div>Cbc0038I Knapsack was tried 2 times and created 0 cuts of which 0 were active after adding rounds of cuts (0.016 seconds)</div>
<div>Cbc0038I Clique was tried 2 times and created 0 cuts of which 0 were active after adding rounds of cuts (0.000 seconds)</div><div>Cbc0038I MixedIntegerRounding2 was tried 2 times and created 0 cuts of which 0 were active after adding rounds of cuts (0.031 seconds)</div>
<div>Cbc0038I FlowCover was tried 2 times and created 0 cuts of which 0 were active after adding rounds of cuts (0.000 seconds)</div><div>Cbc0038I TwoMirCuts was tried 1579 times and created 10 cuts of which 1 were active after adding rounds of cuts (3.860 seconds)</div>
<div>Cbc0038I Stored from first was tried 7626 times and created 350 cuts of which 179 were active after adding rounds of cuts (0.000 seconds)</div><div>Cbc0001I Search completed - best objective 184071.9400000001, took 1886804 iterations and 11532 nodes (900.65 seconds)</div>
<div>Cbc0032I Strong branching done 428 times (5741 iterations), fathomed 0 nodes and fixed 0 variables</div><div>Cbc0035I Maximum depth 34, 0 variables fixed on reduced cost</div><div>Cuts at root node changed objective from 156922 to 157294</div>
<div>Probing was tried 3 times and created 0 cuts of which 0 were active after adding rounds of cuts (0.032 seconds)</div><div>Gomory was tried 24 times and created 61 cuts of which 28 were active after adding rounds of cuts (1.650 seconds)</div>
<div>Knapsack was tried 3 times and created 0 cuts of which 0 were active after adding rounds of cuts (0.016 seconds)</div><div>Clique was tried 3 times and created 0 cuts of which 0 were active after adding rounds of cuts (0.000 seconds)</div>
<div>MixedIntegerRounding2 was tried 3 times and created 0 cuts of which 0 were active after adding rounds of cuts (0.031 seconds)</div><div>FlowCover was tried 1 times and created 0 cuts of which 0 were active after adding rounds of cuts (0.000 seconds)</div>
<div>TwoMirCuts was tried 3 times and created 5 cuts of which 0 were active after adding rounds of cuts (0.624 seconds)</div><div><br></div><div>Result - Optimal solution found</div><div><br></div><div>Objective value: 184071.94000000</div>
<div>Enumerated nodes: 11532</div><div>Total iterations: 1886804</div><div>Time (CPU seconds): 901.01</div><div>Time (Wallclock seconds): 901.01</div><div><br></div><div>Total time (CPU seconds): 901.50 (Wallclock seconds): 901.49</div>
</blockquote><div style="color:rgb(0,0,0);font-family:arial,sans-serif;font-size:13px"> ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------</div>
<div style="color:rgb(0,0,0);font-family:arial,sans-serif;font-size:13px"><br></div><div style="color:rgb(0,0,0);font-family:arial,sans-serif;font-size:13px">Things that baffle me:</div><div style="color:rgb(0,0,0);font-family:arial,sans-serif;font-size:13px">
1) It is timing out after 900 seconds instead of 1800</div><div style="color:rgb(0,0,0);font-family:arial,sans-serif;font-size:13px">2) It is reporting 184071.94 as optimal when it has found a solution of 169460.67</div><div style="color:rgb(0,0,0);font-family:arial,sans-serif;font-size:13px">
<br></div><div style="color:rgb(0,0,0);font-family:arial,sans-serif;font-size:13px">I am running with preprocesssing off because I get the following with it on</div><div style="color:rgb(0,0,0);font-family:arial,sans-serif;font-size:13px">
<br></div><blockquote style="color:rgb(0,0,0);font-family:arial,sans-serif;font-size:13px;margin:0px 0px 0px 40px;border:none;padding:0px"><div>Coin0505I Presolved problem not optimal, resolve after postsolve</div><div>Coin0505I Presolved problem not optimal, resolve after postsolve</div>
<div>Cgl0013I Postprocessed model is infeasible - possible tolerance issue - try without preprocessing</div><div>1 relaxed row infeasibilities - summing to 1</div><div>1 relaxed row infeasibilities - summing to 1</div><div>
1 relaxed row infeasibilities - summing to 1</div><div><br></div><div>Result - Stopped on time limit</div><div><br></div><div>Objective value: 173347.10500000</div><div>Lower bound: 159327.768</div>
<div>Gap: 0.09</div><div>Enumerated nodes: 23597</div><div>Total iterations: 4755507</div><div>Time (CPU seconds): 1800.63</div></blockquote><div style="color:rgb(0,0,0);font-family:arial,sans-serif;font-size:13px">
<br></div><div style="color:rgb(0,0,0);font-family:arial,sans-serif;font-size:13px"><br></div><div style="color:rgb(0,0,0);font-family:arial,sans-serif;font-size:13px">Am I doing something wrong?</div></div>