Matrix: LPnetlib/lpi_gosh
Description: Netlib LP problem gosh: minimize c'*x, where Ax=b, lo<=x<=hi
(bipartite graph drawing) |
Matrix properties | |
number of rows | 3,792 |
number of columns | 13,455 |
nonzeros | 99,953 |
structural full rank? | no |
structural rank | 3,790 |
# of blocks from dmperm | 130 |
# strongly connected comp. | 105 |
explicit zero entries | 0 |
nonzero pattern symmetry | 0% |
numeric value symmetry | 0% |
type | real |
structure | rectangular |
Cholesky candidate? | no |
positive definite? | no |
author | R. Main |
editor | J. Chinneck |
date | 1993 |
kind | linear programming problem |
2D/3D problem? | no |
Additional fields | size and type |
b | full 3792-by-1 |
c | full 13455-by-1 |
lo | full 13455-by-1 |
hi | full 13455-by-1 |
z0 | full 1-by-1 |
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): PROBLEM DESCRIPTION ------------------- GOSH, GRAN, PANG: these very large, large, and medium size models, respectively, problems arose from British Petroleum operations models. Contributor: Roger Main, BP Oil. Name Rows Cols Nonzeros Bounds Notes gosh 3793 10733 97257 B FR 242 free cols Added to Netlib on Sept. 19, 1993
Ordering statistics: | result |
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD | 4,605,419 |
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD | 275,933 |
SVD-based statistics: | |
norm(A) | 323.672 |
min(svd(A)) | 6.28529e-16 |
cond(A) | 5.14968e+17 |
rank(A) | 3,790 |
sprank(A)-rank(A) | 0 |
null space dimension | 2 |
full numerical rank? | no |
singular value gap | 5.53499e+11 |
singular values (MAT file): | click here |
SVD method used: | s = svd (full (A)) ; |
status: | ok |
For a description of the statistics displayed above, click here.
Maintained by Tim Davis, last updated 12-Mar-2014.
Matrix pictures by cspy, a MATLAB function in the CSparse package.
Matrix graphs by Yifan Hu, AT&T Labs Visualization Group.