| Matrix properties | |
| number of rows | 2,000 |
| number of columns | 2,000 |
| nonzeros | 23,556 |
| structural full rank? | yes |
| structural rank | 2,000 |
| # of blocks from dmperm | 1 |
| # strongly connected comp. | 1 |
| entries not in dmperm blocks | 0 |
| explicit zero entries | 0 |
| nonzero pattern symmetry | symmetric |
| numeric value symmetry | symmetric |
| type | binary |
| structure | symmetric |
| Cholesky candidate? | yes |
| positive definite? | no |
| author | C. Helmberg |
| editor | Y. Ye |
| date | 1996 |
| kind | duplicate undirected random graph |
| 2D/3D problem? | no |
Notes:
This matrix is the nonzero pattern of Gset/G39
| Ordering statistics: | AMD | METIS |
| nnz(chol(P*(A+A'+s*I)*P')) | 240,691 | 287,194 |
| Cholesky flop count | 9.4e+07 | 1.1e+08 |
| nnz(L+U), no partial pivoting | 479,382 | 572,388 |
| nnz(V) for QR, upper bound nnz(L) for LU | 1,392,345 | 1,027,951 |
| nnz(R) for QR, upper bound nnz(U) for LU | 1,614,921 | 1,667,202 |
Maintained by Tim Davis, last updated 04-May-2008.
Matrix pictures by cspy, a MATLAB function in the CSparse package.
Matrix graphs by Yifan Hu, AT&T Labs Visualization Group.