[Bonmin] how to read this bonmin log

Matthew Galati magh at lehigh.edu
Sun Nov 16 08:22:41 EST 2008


Hi - it seems that Bonmin failed on my problem.

My question is, from this log, did Bonmin find a feasible (and perhaps 
locally optimal) solution?

If so, is it the one listed at the bottom of the log? 25582233.86109485? 
Or is that a bound for some relaxation?




LOG:


******************************************************************************
This program contains Ipopt, a library for large-scale nonlinear 
optimization.
 Ipopt is released as open source code under the Common Public License 
(CPL).
         For more information visit http://projects.coin-or.org/Ipopt
******************************************************************************

NLP0012I
              Num      Status      Obj             It       time
NLP0013I     1        OPT         -2.618034021090574      17       0.020001
OA0003I New best feasible of -2.50014 found after 0.020001 sec.
Cbc0012I Integer solution of -2.50014 found by nonlinear programm after 
0 iterat
ions and 0 nodes (0.02 seconds)
Cbc0031I 1 added rows had average density of 2
Cbc0013I At root node, 0 cuts changed objective from -2.61803 to 
-2.61803 in 1 p
asses
Cbc0014I Cut generator 0 (NLP solution based oa cuts) - 0 row cuts, 0 
column cut
s (0 active)
Cbc0014I Cut generator 1 (Mixed Integer Gomory) - 0 row cuts, 0 column 
cuts (0 a
ctive)
Cbc0014I Cut generator 2 (Probing) - 0 row cuts, 1 column cuts (1 active)
Cbc0014I Cut generator 3 (Mixed Integer Rounding) - 0 row cuts, 0 column 
cuts (0
 active)
Cbc0014I Cut generator 4 (Cover) - 0 row cuts, 0 column cuts (0 active)
Cbc0014I Cut generator 5 (Clique) - 0 row cuts, 0 column cuts (0 active)
Cbc0014I Cut generator 6 (Flow Covers) - 0 row cuts, 0 column cuts (0 
active)
Cbc0014I Cut generator 7 (Outer Approximation decomposition.) - 0 row 
cuts, 0 co
lumn cuts (0 active)
Cbc0014I Cut generator 8 (Outer Approximation feasibility check.) - 1 
row cuts,
0 column cuts (0 active)
Cbc0001I Search completed - best objective -2.500141411336584, took 0 
iterations
 and 0 nodes (0.02 seconds)
Cbc0035I Maximum depth 0, 0 variables fixed on reduced cost
 Outer Approximation feasibility check. was tried 1 times and created 1 
cuts of
which 0 were active after adding rounds of cuts

bonmin: Optimal

        "Finished"


******************************************************************************
This program contains Ipopt, a library for large-scale nonlinear 
optimization.
 Ipopt is released as open source code under the Common Public License 
(CPL).
         For more information visit http://projects.coin-or.org/Ipopt
******************************************************************************

NLP0012I
              Num      Status      Obj             It       time
NLP0013I     1        FAILED      25582233.86109485       3000     1189.17
NLP0014I     r1       FAILED      25582233.86109485       3000     1172.15
Ipopt exited with error code -1 Maximum iterations exceeded




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