Opened 5 years ago

Closed 7 weeks ago

#145 closed task (migrated)

Infeasibility issue in MIP model built using flopCpp

Reported by: krakesh.iitk Owned by: tkr
Priority: major Component: Cbc
Version: 2.7 Keywords: Infeasibility, Mixed Integer Programming
Cc: krakesh.iitk@…

Description

Hi,

I am solving an assignment and scheduling problem which is MIP and calling OsiCbcSolverInterface? from flopCpp to solve it. The solver is throwing that 'The LP relaxation is infeasible and too expensive'. I like to know if there is any functionality in COIN cbc library to check which constraint or group of constraints are causing infeasibility and also how to deal with these infeasibility issues in COIN environment. I know this functinality is available in CPLEX where CPLEX allows users to remove IISs(Irreducible Infeasibility Sets) but could not find it in COIN. May be I am completely unaware that this functionality does exist in COIN but I am unable to locate it. So please help to resolve this.

Thanks, Rakesh

Attachments (2)

FEMathModel_Phase2.lp (262.9 KB) - added by krakesh.iitk 5 years ago.
.lp file which contains math model which I am trying to solve
FEMathModel_Phase2.mps (696.3 KB) - added by krakesh.iitk 5 years ago.
this is same model in .mps format as .lp format may not be as stable as .mps

Download all attachments as: .zip

Change History (3)

Changed 5 years ago by krakesh.iitk

.lp file which contains math model which I am trying to solve

Changed 5 years ago by krakesh.iitk

this is same model in .mps format as .lp format may not be as stable as .mps

comment:1 Changed 7 weeks ago by stefan

  • Resolution set to migrated
  • Status changed from new to closed

This ticket has been migrated to GitHub and will be resolved there: https://github.com/coin-or/Cbc/issues/145

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