MOPLIB (short for Multi-Objective Problem LIBrary) is a problem library for multi-objective linear, multi-objective (mixed) integer and vector linear programs. The name MOPLIB intentionally resembles and was inspired by the (single-objective) mixed integer problem library MIPLIB. The goal behind MOPLIB is to offer problem instances for available multi-objective solvers modelling a wide variety of applications as well as to support an input format for multi-objective problems. The long-term goal is to make it into a standard test set to be able to compare the performance of different available solvers.
MOPLIB was coined and is currently maintained by Andreas Löhne and Sebastian Schenker. If you develop a solver for multi-criteria optimization or vector optimization or if you use available solvers and you would like to contribute to MOPLIB, please do not hesitate to contact us.
|11/Mar/2016||First instances (.mop files) added.|
|01/04/2016||New instances added.|
|02/06/2016||New (molp) instances added (contributed by László Csirmaz)|
Currently two file formats (.mop and .vlp) are supported by MOPLIB.
The .vlp input format is an extension of the GLPK LP/MIP format. For more information see the VLP description.
MOPLIB distinguishes the following problem classes:
|Multi-objective linear program||molp||Several linear objectives; feasible region is a convex polytope/polyhedron;|
|Multi-objective binary program||mobp||Several linear objectives; feasible region is a convex polytope/polyhedron; all variables are restricted to be binary;|
|Multi-objective integer program||moip||Several linear objectives; feasible region is a convex polytope/polyhedron; all variables are restricted to be integer;|
|Multi-objective mixed integer program||momip||Several linear objectives; feasible region is a convex polytope/polyhedron; some but not all of the variables are restricted to be integer;|
|Vector linear program||vlp||Minimization (or maximization) is defined w.r.t. partial ordering induced by a polyhedral cone; it generalizes multi-objective linear programs;|
Bensolve is a vector and multi-objective linear programming solver supporting the .vlp input format and solving instances of the problem classes: molp, vlp
Inner is a multi-objective linear programming solver supporting the .vlp input format and solving instances of the problem class: molp
PolySCIP is a multi-objective integer and linear programming solver supporting the .mop input format and solving instances of the problem classes: molp, mobp, moip (,momip experimentally)
All test instances come without any warranty. You are free to use, copy and change them for your research/work. We would kindly ask you to acknowledge the MOPLIB in your publication if you use some of the test instances.
The following notation will be used:
|class||problem class the instance belongs to|
|objs||number of objectives of the instance|
|vars||number of variables of the instance|
|cons||number of constraints of the instance|
|description (optional)||string describing the instance|
|.mop||file format is MOP|
|.vlp||file format is VLP|
The naming of an instance comprises of the above identifiers in the following way:
The following instances come without any guarantee. They can be downloaded and used for free. If you use them for your research, we would appreciate a reference to MOPLIB in your publication.