<div dir="ltr"><div><div><div><div><div>Hello,<br><br></div>I'm using the PuLP library to run Cbc. On my latest installation, I've decided to try Cbc 2.8.10. Running the PuLP test suite, I've noticed that the pulpTest060 test failed on both the 2.8.10 release and the current stable/2.8 version.<br>
<br></div>The mps file that results from the pulpTest060 test is:<br><br><div style="margin-left:40px">*SENSE:Minimize<br>NAME MODEL<br>ROWS<br> N OBJ<br> L C0000000<br> G C0000001<br> E C0000002<br>COLUMNS<br>
X0000000 OBJ 1.00000e+00<br> MARK 'MARKER' 'INTORG'<br> X0000001 C0000001 1.00000e+00<br> X0000001 C0000000 1.00000e+00<br> MARK 'MARKER' 'INTEND'<br>
MARK 'MARKER' 'INTORG'<br> X0000002 C0000000 1.00000e+00<br> X0000002 C0000002 -1.00000e+00<br> MARK 'MARKER' 'INTEND'<br> MARK 'MARKER' 'INTORG'<br>
X0000003 C0000001 1.00000e+00<br> X0000003 C0000002 1.00000e+00<br> MARK 'MARKER' 'INTEND'<br>RHS<br> RHS C0000000 5.20000e+00<br> RHS C0000001 1.03000e+01<br>
RHS C0000002 7.40000e+00<br>BOUNDS<br> FX BND X0000000 0.00000e+00<br> UP BND X0000001 4.00000e+00<br> LO BND X0000002 -1.00000e+00<br> UP BND X0000002 1.00000e+00<br> UP BND X0000003 1.00000e+01<br>
ENDATA<br><br></div>The command line executed for running this test is:<br><br><div style="margin-left:40px">cbc /tmp/27068-pulp.mps branch printingOptions rows solution /tmp/27068-pulp.sol<br></div><br></div>The stdout for this problem and releases/2.8.10 r2045 is:<br>
<br><div style="margin-left:40px">Welcome to the CBC MILP Solver <br>Version: 2.8.10 <br>Build Date: Aug 18 2014 <br>Revision Number: 2056 <br><br>command line - ./cbc /tmp/27068-pulp.mps branch printingOptions rows solution /tmp/27068-pulp.sol (default strategy 1)<br>
At line 2 NAME MODEL<br>At line 3 ROWS<br>At line 8 COLUMNS<br>At line 22 RHS<br>At line 26 BOUNDS<br>At line 32 ENDATA<br>Problem MODEL has 3 rows, 4 columns and 6 elements<br>Coin0008I MODEL read with 0 errors<br>
Continuous objective value is 0 - 0.00 seconds<br>Cgl0004I processed model has 1 rows, 2 columns (2 integer) and 2 elements<br>1 infeasibilities<br>Problem is infeasible!<br>Option for printingOptions changed from normal to rows<br>
Total time (CPU seconds): 0.00 (Wallclock seconds): 0.00<br></div><br></div>The solution file for this problem and releases/2.8.10 r2045 is:<br><br><div style="margin-left:40px">Optimal - objective value 0.00000000<br>
0 C0000000 5 0<br> 1 C0000001 12.4 0<br> 2 C0000002 7.4 0<br> 0 X0000000 0 1<br>
1 X0000001 4 0<br> 2 X0000002 1 0<br> 3 X0000003 8.4 0<br></div><br></div>The stdout and solution file are almost the same for stable/2.8 r2056 except for the version value.<br>
<div><br><div>The expected result is that the solution file should start with "Infeasible" or "Unbounded" instead of "Optimal" for this specific problem.<br><br></div><div>Regards,<br><br>Rémy<br>
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