Matrix: GHS_psdef/apache2
Description: SPD matrix (finite difference 3D) from APACHE small
(undirected graph drawing) |
Matrix properties | |
number of rows | 715,176 |
number of columns | 715,176 |
nonzeros | 4,817,870 |
structural full rank? | yes |
structural rank | 715,176 |
# of blocks from dmperm | 1 |
# strongly connected comp. | 1 |
explicit zero entries | 0 |
nonzero pattern symmetry | symmetric |
numeric value symmetry | symmetric |
type | real |
structure | symmetric |
Cholesky candidate? | yes |
positive definite? | yes |
author | |
editor | N. Gould, Y. Hu, J. Scott |
date | 2006 |
kind | structural problem |
2D/3D problem? | yes |
Ordering statistics: | result |
nnz(chol(P*(A+A'+s*I)*P')) with AMD | 177,279,446 |
Cholesky flop count | 2.8e+11 |
nnz(L+U), no partial pivoting, with AMD | 353,843,716 |
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD | 401,332,351 |
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD | 733,526,338 |
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.