Matrix: HB/shl_0
Description: UNSYMMETRIC BASIS FROM LP PROBLEM SHELL
(bipartite graph drawing) | (graph drawing of A+A') |
Matrix properties | |
number of rows | 663 |
number of columns | 663 |
nonzeros | 1,687 |
structural full rank? | yes |
structural rank | 663 |
# of blocks from dmperm | 663 |
# strongly connected comp. | 4 |
explicit zero entries | 0 |
nonzero pattern symmetry | 0% |
numeric value symmetry | 0% |
type | integer |
structure | unsymmetric |
Cholesky candidate? | no |
positive definite? | no |
author | M. Saunders |
editor | A. Curtis, I. Duff, J. Reid |
date | 1978 |
kind | optimization problem sequence |
2D/3D problem? | no |
Notes:
next: HB/shl_200 first: HB/shl_0
Ordering statistics: | result |
nnz(chol(P*(A+A'+s*I)*P')) with AMD | 13,501 |
Cholesky flop count | 8.4e+05 |
nnz(L+U), no partial pivoting, with AMD | 26,339 |
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD | 24,451 |
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD | 111,521 |
SVD-based statistics: | |
norm(A) | 9565.84 |
min(svd(A)) | 1.11579e-05 |
cond(A) | 8.57317e+08 |
rank(A) | 663 |
sprank(A)-rank(A) | 0 |
null space dimension | 0 |
full numerical rank? | yes |
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.