Matrix: GHS_psdef/apache1
Description: SPD matrix (finite difference 3D) from APACHE small
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| Matrix properties | |
| number of rows | 80,800 |
| number of columns | 80,800 |
| nonzeros | 542,184 |
| structural full rank? | yes |
| structural rank | 80,800 |
| # 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 | 12,720,302 |
| Cholesky flop count | 8.4e+09 |
| nnz(L+U), no partial pivoting, with AMD | 25,359,804 |
| nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD | 28,420,466 |
| nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD | 51,283,650 |
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.