Matrix: HB/685_bus
Description: S ADMITTANCE MATRIX 685 BUS POWER SYSTEM, D.J.TYLAVSKY, JULY 1985.
| Matrix properties | |
| number of rows | 685 |
| number of columns | 685 |
| nonzeros | 3,249 |
| structural full rank? | yes |
| structural rank | 685 |
| # 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 | real |
| structure | symmetric |
| Cholesky candidate? | yes |
| positive definite? | yes |
| author | D. Tylavsky |
| editor | I. Duff, R. Grimes, J. Lewis |
| date | 1985 |
| kind | power network problem |
| 2D/3D problem? | no |
| Ordering statistics: | AMD | METIS |
| nnz(chol(P*(A+A'+s*I)*P')) | 3,650 | 4,023 |
| Cholesky flop count | 2.5e+04 | 3.3e+04 |
| nnz(L+U), no partial pivoting | 6,615 | 7,361 |
| nnz(V) for QR, upper bound nnz(L) for LU | 5,731 | 7,080 |
| nnz(R) for QR, upper bound nnz(U) for LU | 11,153 | 13,294 |
Maintained by Tim Davis, last updated 30-Sep-2008.
Matrix pictures by cspy, a MATLAB function in the CSparse package.
Matrix graphs by Yifan Hu, AT&T Labs Visualization Group.