[Cbc-tickets] [COIN-OR Branch-and-Cut MIP Solver] #95: not finding glable optimum with an SOS2 formulation solving using CBC
COIN-OR Branch-and-Cut MIP Solver
coin-trac at coin-or.org
Mon Jul 26 15:51:52 EDT 2010
#95: not finding glable optimum with an SOS2 formulation solving using CBC
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Reporter: ylee77 | Type: defect
Status: new | Priority: major
Version: | Keywords:
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Hello,
I am confronting a problem that the solution obtained from CBC doesn't
coincide with what I obtained from CPLEX. I actually tried two ways to
code up the SOS2 formulation and they both return same values, with a
claim that the search is complete and the solution is proven optimum. Yet
I can see the solution is not optimum and is different from what CPLEX
get. I wonder whether there is some internal problem inside the branch-
and-bound. Thanks a lot.
Attached is
1. the problem formulation
2. the input data set
3. a piece of code that includes the function "
PfofModel_OptimizeMaxParticipation" which I coded the SOS2 formulation and
using branch and bound to solve it.
Sincerely,
Yu-Ching
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Ticket URL: <https://projects.coin-or.org/Cbc/ticket/95>
COIN-OR Branch-and-Cut MIP Solver <http://projects.coin-or.org/Cbc>
An LP-based branch-and-cut MIP solver.
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