LPnetlib/lpi_vol1
Netlib LP problem vol1: minimize c'*x, where Ax=b, lo<=x<=hi
Name 
lpi_vol1 
Group 
LPnetlib 
Matrix ID 
730 
Num Rows

323 
Num Cols

464 
Nonzeros

1,646 
Pattern Entries

1,646 
Kind

Linear Programming Problem 
Symmetric

No 
Date

1993 
Author

T. Baker 
Editor

J. Chinneck 
Structural Rank 
323 
Structural Rank Full 
true 
Num Dmperm Blocks

13 
Strongly Connect Components

1 
Num Explicit Zeros

0 
Pattern Symmetry

0% 
Numeric Symmetry

0% 
Cholesky Candidate

no 
Positive Definite

no 
Type

real 
SVD Statistics 
Matrix Norm 
1.011726e+04 
Minimum Singular Value 
2.096247e01 
Condition Number 
4.826369e+04

Rank 
323 
sprank(A)rank(A) 
0 
Null Space Dimension 
0 
Full Numerical Rank? 
yes 
Download Singular Values 
MATLAB

Download 
MATLAB
Rutherford Boeing
Matrix Market

Notes 
An infeasible Netlib LP problem, in lp/infeas. For more information
send email to netlib@ornl.gov with the message:
send index from lp
send readme from lp/infeas
The lp/infeas directory contains infeasible linear programming test problems
collected by John W. Chinneck, Carleton Univ, Ontario Canada. The following
are relevant excerpts from lp/infeas/readme (by John W. Chinneck):
In the following, IIS stands for Irreducible Infeasible Subsystem, a set
of constraints which is itself infeasible, but becomes feasible when any
one member is removed. Isolating an IIS from within the larger set of
constraints defining the model is one analysis approach.
PROBLEM DESCRIPTION

CHEMCOM, QUAL, REFINERY, REACTOR, VOL1: medium size problems derived
from a petrochemical plant model. Doctored to generate infeasibility
due to inability to meet volume or quality restrictions. With the
exception of REACTOR, these are highly volatile problems, yielding IISs
of varying sizes when different IIS isolation algorithms are applied.
See Chinneck [1993] for further discussion. Contributor: Tom Baker,
Chesapeake Decision Sciences.
Name Rows Cols Nonzeros Bounds Notes
vol1 324 464 1714 B FX
REFERENCES

J.W. Chinneck (1993). "Finding the Most Useful Subset of Constraints
for Analysis in an Infeasible Linear Program", technical report
SCE9307, Systems and Computer Engineering, Carleton University,
Ottawa, Canada.
