Matrix: Grund/b2_ss
Description: Unsymmetric Matrix b2_ss, F. Grund, Dec 1994.
(bipartite graph drawing) | (graph drawing of A+A') |
Matrix properties | |
number of rows | 1,089 |
number of columns | 1,089 |
nonzeros | 3,895 |
structural full rank? | yes |
structural rank | 1,089 |
# of blocks from dmperm | 249 |
# strongly connected comp. | 1 |
explicit zero entries | 333 |
nonzero pattern symmetry | 1% |
numeric value symmetry | 0% |
type | real |
structure | unsymmetric |
Cholesky candidate? | no |
positive definite? | no |
author | F. Grund |
editor | F. Grund |
date | 1997 |
kind | chemical process simulation problem |
2D/3D problem? | no |
Additional fields | size and type |
b | full 1089-by-1 |
Ordering statistics: | result |
nnz(chol(P*(A+A'+s*I)*P')) with AMD | 85,194 |
Cholesky flop count | 1.7e+07 |
nnz(L+U), no partial pivoting, with AMD | 169,299 |
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD | 3,895 |
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD | 9,864 |
Note that all matrix statistics (except nonzero pattern symmetry) exclude the 333 explicit zero entries.
SVD-based statistics: | |
norm(A) | 209350 |
min(svd(A)) | 2.73159e-07 |
cond(A) | 7.66404e+11 |
rank(A) | 1,089 |
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.