[Couenne-tickets] [Couenne, a solver for non-convex MINLP problems] #8: couenne says "infeasable" for feasable problem

[Couenne, a solver for non-convex MINLP problems]

#8: couenne says "infeasable" for feasable problem
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  Reporter:  sergm       |       Owner:  pbelotti
      Type:  defect      |      Status:  assigned
  Priority:  major       |   Milestone:          
 Component:  component1  |     Version:          
Resolution:              |    Keywords:          
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Comment (by pbelotti):

 Apologies for the long delay in responding. The instance seems to have
 indeed serious numerical issues, above all a multiplier ~ 1e10 in one of
 the constraints. I believe this triggers a few problems in the solution,
 but there were indeed some wrong bound reduction -- thanks for pointing
 this out. Unfortunately, depending on the feasibility tolerance (which is
 set through the option feas_tolerance in the option file couenne.opt) the
 optimal solution found changes, and I believe the same would happen to
 BARON. A similar behavior is observed in the original globallib/bearing.

 The stable/0.3 version contains a fix that works on the two instances. I
 haven't tried solving Gaussoid fully, but a solution is found and hence
 the problem is no longer infeasible.

-- 
Ticket URL: <https://projects.coin-or.org/Couenne/ticket/8#comment:3>
Couenne, a solver for non-convex MINLP problems <https://projects.coin-or.org/Couenne>
Couenne, a solver for non-convex MINLP problems