[Dip] optimal in doCut and infeasible in B&C&P(doPriceCut)

[Shahin Gelareh]

Hi everybody

I have got a problem which is decomposed and uses DIP for testing the
numerical behaviour under B&C&P(doPriceCut) and doCut.

branch and price log is the folloinwg which declares infeasibility:
Model core nCols= 35 nRows = 99
==  Welcome to the Abstract Library for Parallel Search (ALPS)
==  Copyright 2000-2011 Lehigh University and others
==  All Rights Reserved.
==  Distributed under the Eclipse Public License 1.0
==  Version: Trunk (unstable)
==  Build Date: Jul  2 2012
Alps0250I Starting search ...
Process Node 0 (algo = PRICE_AND_CUT, phaseLast = PHASE_UNKNOWN) gLB = -INF
gUB =  INF gap =  INF time = 1.560
phase = PHASE_PRICE1
Processing Node   0 algo= PRICE_AND_CUT phase= PHASE_PRICE1 c=    0 p=    1
LB=     -1.000 UB=      9.000 nodeLB=     -1.000 gLB=     -1.000 gUB=
   INF lpGap=     10.000 ipGap=        INF time=       1.66
Processing Node   0 algo= PRICE_AND_CUT phase= PHASE_PRICE1 c=    0 p=    2
LB=      0.000 UB=      6.500 nodeLB=      0.000 gLB=      0.000 gUB=
   INF lpGap=      6.500 ipGap=        INF time=       1.76
Processing Node   0 algo= PRICE_AND_CUT phase= PHASE_PRICE1 c=    0 p=    3
LB=      1.400 UB=      4.800 nodeLB=      1.400 gLB=      1.400 gUB=
   INF lpGap=      2.429 ipGap=        INF time=       1.85
Processing Node   0 algo= PRICE_AND_CUT phase= PHASE_PRICE1 c=    0 p=    4
LB=      4.000 UB=      4.000 nodeLB=      4.000 gLB=      4.000 gUB=
   INF lpGap=      0.000 ipGap=        INF time=       1.90

Alps0202I Problem is infeasible. 1 nodes processed, 0 nodes left
Alps0264I No solution found
Alps0265I Number of nodes fully processed:          1
Alps0266I Number of nodes partially processed:      0
Alps0267I Number of nodes branched:                 0
Alps0268I Number of nodes pruned before processing: 0
Alps0270I Number of nodes left:                     0
Alps0272I Tree depth: 0
Alps0274I Search CPU time: 0.40 seconds
Alps0278I Search wall-clock time: 0.40 seconds

========== DECOMP Statistics [BEGIN]: =========
Total Decomp          =       0.34    100.00     1  0.34
Total Solve Relax     =       0.31     90.00    25  0.08
Total Solve Relax App =       0.00      0.00    25  0.00
Total Solution Update =       0.00      1.18     4  0.00
Total Generate Cuts   =       0.00      0.00     0  0.00
Total Generate Vars   =       0.03      9.12     4  0.02
Total Compress Cols   =       0.00      0.00     0  0.00
========== DECOMP Statistics [END  ]: =========
Status= 5 BestLB=        -INF BestUB=        INF Nodes=      1 SetupCPU=
1.50 SolveCPU= 0.52 TotalCPU= 2.03 SetupReal= 1.50 SolveReal= 0.52
TotalReal=
 2.03



but branch and cut ends to following log:

....
Alps0208I Search completed.
Alps0261I Best solution found had quality -16 and was found at depth 1
Alps0265I Number of nodes fully processed:          3
Alps0266I Number of nodes partially processed:      0
Alps0267I Number of nodes branched:                 1
Alps0268I Number of nodes pruned before processing: 0
Alps0270I Number of nodes left:                     0
Alps0272I Tree depth: 1
Alps0274I Search CPU time: 0.44 seconds
Alps0278I Search wall-clock time: 0.44 seconds

========== DECOMP Statistics [BEGIN]: =========
Total Decomp          =       0.39    100.00     3  0.29
Total Solve Relax     =       0.00      0.00     0  0.00
Total Solve Relax App =       0.00      0.00     0  0.00
Total Solution Update =       0.01      1.27     7  0.00
Total Generate Cuts   =       0.12     29.52     5  0.02
Total Generate Vars   =       0.00      0.00     0  0.00
Total Compress Cols   =       0.00      0.00     0  0.00
========== DECOMP Statistics [END  ]: =========
Status= 0 BestLB=   -16.00000 BestUB=  -16.00000 Nodes=      3 SetupCPU=
1.06 SolveCPU= 0.56 TotalCPU= 1.62 SetupReal= 1.06 SolveReal= 0.56
TotalReal=
 1.62
Optimal Solution



how to interpret this? the optimal solution of doCut is correct.
I have difficulties to understand what goes wrong that makes the problem
infeasible.

I appreciate any comment.

regards,
Shahin
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