[Couenne-tickets] [Couenne] #38: Couenne says "infeasible problem" when there is binary variables!

[Couenne]

#38: Couenne says "infeasible problem" when there is binary variables!
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 Reporter:  Burcu    |      Owner:  pbelotti
     Type:  defect   |     Status:  new
 Priority:  blocker  |  Milestone:
Component:  Couenne  |    Version:
 Keywords:           |
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 Dear All,

 It is a nonlinear MIP model with continuous, binary and integer variables.
 When I try to solve it with couenne it says that it is infeasible. But I
 have already found an initial solution by hand that suits model. I am
 attaching this hand-made initial solution.

 I just made a search through the net and found out that Couenne gave
 "infeasible solution" for other people's models when there are binary
 variables. I changed my binary variables to continious variables, and
 couenne works! But ofcourse the result is meaningless. Would you please
 help me to solve the model with my binar variables?

 I am attaching the model and data in AMPL format. Below you can see the
 result page, when I run the model with binary variables. Thank you!


 ampl: model C:\Users\BURCU\Desktop\Tez\AMPL_TEZ\Facility-baFN4.mod; data
 C:\Users\BURCU\Desktop\Tez\AMPL_TEZ\Facility-baFN4.dat; solve;
 Couenne 0.5.6 -- an Open-Source solver for Mixed Integer Nonlinear
 Optimization
 Mailing list: couenne at list.coin-or.org
 Instructions: http://www.coin-or.org/Couenne
 couenne:
 ANALYSIS TEST: Reformulating problem: 0.5 seconds
 NLP0012I
               Num      Status      Obj             It       time
 Location
 NLP0014I             1      INFEAS 0.96000003       70 60.098
 Loaded instance "C:\Users\BURCU\AppData\Local\Temp\at7600.nl"
 Constraints:         3796
 Variables:           2271 (1121 integer)
 Auxiliaries:         1474 (287 integer)

 Coin0506I Presolve 73 (-3599) rows, 78 (-3667) columns and 261 (-10185)
 elements
 Clp0006I 0  Obj 0 Primal inf 15608 (32)
 Clp0006I 33  Obj 3.0982e-014 Primal inf 2.999994 (6)
 Clp0006I 35  Obj 3.0988e-014
 Clp0000I Optimal - objective value 0
 Clp0032I Optimal objective 0 - 35 iterations time 0.032, Presolve 0.02
 Clp0000I Optimal - objective value 0
 NLP Heuristic: NLP0014I             2      INFEAS 0.99999999       32
 1.229
 no solution.
 Clp0000I Optimal - objective value 0
 Optimality Based BT: 3 improved bounds
 Probing: 23 improved bounds
 NLP Heuristic: time limit reached.
 Cbc0013I At root node, 0 cuts changed objective from 0 to 0 in 1 passes
 Cbc0014I Cut generator 0 (Couenne convexifier cuts) - 0 row cuts average
 0.0 elements, 57 column cuts (57 active)
 Cbc0010I After 0 nodes, 1 on tree, 1e+050 best solution, best possible
 -1.7976931e+308 (22.91 seconds)
 Optimality Based BT: 0 improved bounds
 Optimality Based BT: 0 improved bounds
 Optimality Based BT: 0 improved bounds
 Optimality Based BT: 0 improved bounds
 Cbc0001I Search completed - best objective 1e+050, took 298 iterations and
 62 nodes (164.06 seconds)
 Cbc0035I Maximum depth 10, 0 variables fixed on reduced cost

         "Finished"

 Linearization cuts added at root node:       3672
 Linearization cuts added in total:           3672  (separation time:
 0.016s)
 Total solve time:                         164.125s (164.125s in branch-
 and-bound)
 Lower bound:                                 -inf
 Upper bound:                                  inf  (gap: --)
 Branch-and-bound nodes:                        62
 Performance of                           FBBT:        0.266s,       64
 runs. fix:          0 shrnk:   0.826375 ubd:    7.02954 2ubd:    2.46442
 infeas:         24

 couenne: Infeasible problem

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Ticket URL: <https://projects.coin-or.org/Couenne/ticket/38>
Couenne <https://projects.coin-or.org/Couenne>
Couenne, a solver for non-convex MINLP