[Clp] OsiClp vs Clp status on infeasible problem

[Matthew Galati]

This same thing is happening in many cases now. Is there some internal CLP
flag I can check to see if the internal status is set to infeasible? Perhaps
there is just a bug in the transfer to the OsiClp status?





The following LP when run against CLP exe seems to correctly find the
> problem infeasible. However, when run inside OsiClp with resolve( ) - warm
> started after many other previous iterations, it declares the problem
> optimal (by status), despite the log which seems to show it as infeasible.
>
> https://coral.ie.lehigh.edu/~magh/tmp/PRICE_AND_CUT_masterProb.n12.c0.p0.lp<https://coral.ie.lehigh.edu/%7Emagh/tmp/PRICE_AND_CUT_masterProb.n12.c0.p0.lp>
>
> Log running as direct executable.
>
> [magala at orclus71 MMKP]$ ../../../bin/clp
> PRICE_AND_CUT_masterProb.n12.c0.p0.lp
> Coin LP version trunk, build Oct 25 2009
> command line - ../../../bin/clp PRICE_AND_CUT_masterProb.n12.c0.p0.lp
> Presolve 884 (-7126) rows, 53 (-8069) columns and 20791 (-78748) elements
> 0  Obj -67321.6 Primal inf 1.23658 (4) Dual inf 5.21256e+06 (53)
> 10  Obj -95950.4 Primal inf 160.616 (162)
> 12  Obj -93938.6 Primal inf 139.824 (204)
> 13  Obj -93851.8 Primal inf 131.17 (211)
> 16  Obj -74041.9 Primal inf 4979.62 (190)
> 17  Obj -30215 Primal inf 33506.3 (215)
> 17  Obj -30215 Primal inf 33506.3 (215)
> 18  Obj -29773 Primal inf 33795.2 (211)
> 18  Obj -29773 Primal inf 33795.2 (211)
> 18  Obj -29773 Primal inf 33795.2 (211)
> 18  Obj -29773 Primal inf 33795.2 (211)
> 18  Obj -29773 Primal inf 33795.2 (211)
> 18  Obj -29773 Primal inf 33795.2 (211)
> 18  Obj -29773 Primal inf 33795.2 (211)
> Primal infeasible - objective value -29773
> Presolved problem not optimal, resolve after postsolve
> After Postsolve, objective -29773, infeasibilities - dual 263995 (1),
> primal 115893 (467)
> PrimalInfeasible objective -29773.04364 - 36 iterations time 0.202,
> Presolve 0.15
>
>
> Log running within OsiClp:
>
> Coin0506I Presolve 884 (-7126) rows, 53 (-8069) columns and 20791 (-78748)
> elements
> Clp1001I Initial range of elements is 1 to 2581
> Clp1003I Final range of elements is 0.636117 to 1
> Clp0022I Absolute values of scaled rhs range from 0.774893 to 1.06895,
> minimum gap 1e+100
> Clp0020I Absolute values of scaled objective range from 94854 to 100383
> Clp0021I Absolute values of scaled bounds range from 1 to 1, minimum gap 1
> Clp0006I 0  Obj -98371.9 Primal inf 1356.04 (328) Dual inf 3157.55 (17)
> Clp0006I 184  Obj -97923.4 Primal inf 4676.17 (409)
> Clp0006I 291  Obj 182182 Primal inf 28254 (419)
> Clp0006I 292  Obj 2.37148e+06 Primal inf 246180 (416)
> Clp0006I 293  Obj 3.73415e+06 Primal inf 382285 (416)
> Clp0006I 295  Obj 6.42176e+06 Primal inf 649494 (415)
> Clp0006I 295  Obj 6.42176e+06 Primal inf 649494 (415)
> Clp0006I 295  Obj 6.42176e+06 Primal inf 649494 (415)
> Clp0006I 295  Obj 6.42176e+06 Primal inf 649494 (415)
> Clp0006I 295  Obj 6.42176e+06 Primal inf 649494 (415)
> Clp0023I Possible loop - 5 matches (1f) after 11 checks
> Clp0006I 295  Obj 6.42176e+06 Primal inf 649494 (415)
> Clp0006I 295  Obj 6.42176e+06 Primal inf 649494 (415)
> Clp0006I 295  Obj 6.42176e+06 Primal inf 649494 (415)
> Clp0001I Primal infeasible - objective value 6.42176e+06
> Coin0505I Presolved problem not optimal, resolve after postsolve
> Coin0511I After Postsolve, objective 6.42176e+06, infeasibilities - dual 0
> (0), primal 1.95228e+06 (996)
> Clp1001I Initial range of elements is 1 to 3215
> Clp1003I Final range of elements is 0.288447 to 1
> Clp0022I Absolute values of scaled rhs range from 0.622084 to 1.06895,
> minimum gap 1e+100
> Clp0020I Absolute values of scaled objective range from 89856 to 104359
> Clp0006I 0  Obj 6.42176e+06 Primal inf 1.39856e+06 (996)
> Clp0006I 0  Obj 6.42176e+06 Primal inf 1.39856e+06 (996)
> Clp0006I 0  Obj 6.42176e+06 Primal inf 1.39856e+06 (996)
> Clp0006I 0  Obj 6.42176e+06 Primal inf 1.39856e+06 (996)
> Clp0006I 0  Obj 6.42176e+06 Primal inf 1.39856e+06 (996)
> Clp0006I 0  Obj 6.42176e+06 Primal inf 1.39856e+06 (996)
> Clp0006I 0  Obj 6.42176e+06 Primal inf 1.39856e+06 (996)
> Clp0006I 0  Obj 6.42176e+06 Primal inf 1.39856e+06 (996)
> Solution update n_cols:8122       n_rows: 8010       n_iter: 295
>  time: 1.519
> Iteration Count               : 295
> isAbandoned()                 : 0
> isProvenOptimal()             : 1
> isProvenPrimalInfeasible()    : 0
> isProvenDualInfeasible()      : 0
> isPrimalObjectiveLimitReached : 0
> isDualObjectiveLimitReached   : 0
> isIterationLimitReached       : 0
> MasterObj                     : 6.42176e+06
>
>
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