[Osi-tickets] [COIN-OR Open Solver Interface] #48: OsiCbc forgets message handler

[COIN-OR Open Solver Interface]

#48: OsiCbc forgets message handler
--------------------+-------------------------------------------------------
 Reporter:  stefan  |       Owner:  lou
     Type:  defect  |      Status:  new
 Priority:  minor   |   Milestone:     
Component:  OsiCbc  |     Version:     
 Keywords:          |  
--------------------+-------------------------------------------------------
 Hi,

 when I do a
 {{{
   OsiCbcSolverInterface::passInMessageHandler(mymsghandler);
 }}}
 before an {{{initialSolve()}}} or {{{branchAndBound()}}}, then output
 still goes through the default message handler, i.e., to the screen.

 For an LP this looks like
 {{{
 Coin0506I Presolve 5 (0) rows, 6 (0) columns and 12 (0) elements
 Clp0028I Crash put 0 variables in basis, 0 dual infeasibilities
 Clp0006I 0  Obj 0 Primal inf 900 (3) Dual inf 6e+10 (6)
 Clp0006I 3  Obj 153.675
 Clp0000I Optimal - objective value 153.675
 Coin0511I After Postsolve, objective 153.675, infeasibilities - dual 0
 (0), primal 0 (0)
 Clp0006I 0  Obj 153.675
 Clp0006I 0  Obj 153.675
 Clp0000I Optimal - objective value 153.675
 }}}

 For a MIP, this looks like
 {{{
 Cbc0031I 8 added rows had average density of 42.875
 Cbc0013I At root node, 8 cuts changed objective from 204.368 to 211.666 in
 100 passes
 Cbc0014I Cut generator 0 (Probing) - 0 row cuts (0 active), 0 column cuts
 in 1.188 seconds - new frequency is -100
 Cbc0014I Cut generator 1 (Gomory) - 540 row cuts (8 active), 0 column cuts
 in 0.036 seconds - new frequency is -100
 Cbc0014I Cut generator 2 (Knapsack) - 0 row cuts (0 active), 0 column cuts
 in 0.008 seconds - new frequency is -100
 Cbc0014I Cut generator 3 (Clique) - 0 row cuts (0 active), 0 column cuts
 in 0.000 seconds - new frequency is -100
 Cbc0014I Cut generator 4 (FlowCover) - 0 row cuts (0 active), 0 column
 cuts  in 0.024 seconds - new frequency is -100
 Cbc0014I Cut generator 5 (MixedIntegerRounding2) - 68 row cuts (0 active),
 0 column cuts  in 0.024 seconds - new frequency is -100
 Cbc0010I After 0 nodes, 1 on tree, 1e+50 best solution, best possible
 211.666 (1.40 seconds)
 Cbc0015I Node 1 Obj 211.666 Unsat 7 depth 1
 Cbc0015I Node 2 Obj 211.666 Unsat 8 depth 2
 Cbc0015I Node 3 Obj 211.674 Unsat 3 depth 3
 Cbc0015I Node 4 Obj 211.674 Unsat 3 depth 4
 Cbc0015I Node 5 Obj 211.675 Unsat 2 depth 5
 Cbc0015I Node 6 Obj 212.173 Unsat 2 depth 6
 Cbc0004I Integer solution of 213.711 found after 1037 iterations and 7
 nodes (1.42 seconds)
 Cbc0015I Node 11 Obj 211.666 Unsat 5 depth 2
 Cbc0015I Node 13 Obj 211.983 Unsat 5 depth 3
 Cbc0015I Node 14 Obj 213.347 Unsat 2 depth 4
 Cbc0015I Node 18 Obj 211.667 Unsat 4 depth 1
 Cbc0004I Integer solution of 212.111 found after 1206 iterations and 20
 nodes (1.44 seconds)
 Cbc0001I Search completed - best objective 212.111, took 1206 iterations
 and 20 nodes (1.44 seconds)
 Cbc0032I Strong branching done 146 times (1634 iterations), fathomed 3
 nodes and fixed 5 variables
 Cbc0035I Maximum depth 6, 60 variables fixed on reduced cost
 }}}

 I'm using Osi 0.98, Clp 1.6, and Cbc 2.0, all stable.

 Best,
 Stefan

-- 
Ticket URL: <https://projects.coin-or.org/Osi/ticket/48>
COIN-OR Open Solver Interface <http://projects.coin-or.org/Osi>
An API for a variety of LP and MIP solvers (and more).