bppc6-06

dual-infeasible

The instance

as published

Variables: 3,922
Constraints: 272
Nonzeros: 181,319
Format: MPS, gzipped

Where it comes from

provenance

The source instance's LP relaxation is feasible with a bounded optimum. Removing the elements below makes the objective unbounded, and putting any one of them back makes it bounded again.

Bounds dropped: 12
Rows dropped: 1

What was removed

13 entries

row c6lb of X5.77lb of X5.33lb of X0.191lb of X8.243lb of hub of X0.47lb of X5.178lb of X8.123ub of X3.161lb of X3.104ub of X8.220

12 of 13 shown. The complete list is in the sidecar.

Download

bppc6-06_ub.mps.gz0.47 MiB bppc6-06_ub.meta.json4 KiB

The sidecar carries the full provenance, including the fields this page truncates.

Source instance

Namebppc6-06

Submitted byManuel Iori

Groupbppc

TermsCC BY-SA 4.0

set_partitioning

The models that we attach solve the “bar-relaxation”, also known as the “Bin Packing Problem with Contiguity” or the “P||Cmax with contiguity”. This is one of the most interesting relaxations for two dimensional cutting and packing problems. Its solution by means of an ILP software is the bottleneck of the primal decomposition methods that we attempted in the paper cited below. In detail, the files correspond to model (12)-(15) in the paper, applied to the instances of the Classes 4, 6 and 8 by Martello and Vigo (Management Science, 1998).

Source description quoted from MIPLIB 2017; links and mathematical notation formatted for the web.

View on MIPLIB 2017 →