Submitter | Variables | Constraints | Density | Status | Group | Objective | MPS File |
---|---|---|---|---|---|---|---|
Matias Sørensen | 10863 | 14038 | 3.75757e-04 | easy | coursetimetabling | 74 | comp21-2idx.mps.gz |
Instances comp01-21 of curriculum based course timetabling from the International Timetabling Competition 2007. These are time-assignment models (Stage I of the decomposed model), which are smaller than the full model, but still hard to solve. Solved with COPT 7.0 using up to 12 threads in less than 30 minutes.
Detailed explanation of the following tables can be found here.
Original | Presolved | |
---|---|---|
Variables | 10863 | 10717 |
Constraints | 14038 | 13926 |
Binaries | 10792 | 10646 |
Integers | 71 | 71 |
Continuous | 0 | 0 |
Implicit Integers | 0 | 0 |
Fixed Variables | 0 | 0 |
Nonzero Density | 0.000375757 | 0.000382291 |
Nonzeroes | 57301 | 57055 |
Original | Presolved | |
---|---|---|
Total | 14038 | 13926 |
Empty | 0 | 0 |
Free | 0 | 0 |
Singleton | 53 | 0 |
Aggregations | 0 | 0 |
Precedence | 6529 | 6481 |
Variable Bound | 4802 | 4802 |
Set Partitioning | 2 | 2 |
Set Packing | 0 | 0 |
Set Covering | 341 | 0 |
Cardinality | 92 | 92 |
Invariant Knapsack | 582 | 2463 |
Equation Knapsack | 0 | 0 |
Bin Packing | 0 | 0 |
Knapsack | 0 | 0 |
Integer Knapsack | 0 | 0 |
Mixed Binary | 1566 | 15 |
General Linear | 71 | 71 |
Indicator | 0 | 0 |
Available nonzero structure and decomposition information. Further information can be found here.
Decomposed structure of original problem (dec-file)
Decomposed structure after trivial presolving (dec-file)
value | min | median | mean | max | |
---|---|---|---|---|---|
Components | 2.428135 | ||||
Constraint % | 0.0071800 | 0.305359 | 0.0502657 | 3.63349 | |
Variable % | 0.0279929 | 0.305406 | 0.0746478 | 3.05123 | |
Score | 0.799760 |
Find solutions below. Download the archive containing all solutions from the Download page.
ID | Objective | Exact | Int. Viol | Cons. Viol | Obj. Viol | Submitter | Date | Description |
---|---|---|---|---|---|---|---|---|
1 | 74 | 74 | 0 | 0 | 0 | - | 2018-10-10 | Solution found during MIPLIB2017 problem selection. |
The following instances are most similar to comp21-2idx in the collection. This similarity analysis is based on 100 scaled instance features describing properties of the variables, objective function, bounds, constraints, and right hand sides.
ITC2007 webpage: www.cs.qub.ac.uk/itc2007/
Model reference: @Article{Lach2012,
author="Lach, Gerald
and L{\"u}bbecke, Marco E.",
title="Curriculum based course timetabling: new solutions to Udine benchmark instances",
journal="Annals of Operations Research",
year="2012",
volume="194",
number="1",
pages="255--272",
abstract="We present an integer programming approach to the university course timetabling problem, in which weekly lectures have to be scheduled and assigned to rooms. Students' curricula impose restrictions as to which courses may not be scheduled in parallel. Besides some hard constraints (no two courses in the same room at the same time, etc.), there are several soft constraints in practice which give a convenient structure to timetables; these should be met as well as possible.",
issn="1572-9338",
doi="10.1007/s10479-010-0700-7",
url="http://dx.doi.org/10.1007/s10479-010-0700-7"
}