Matrix: Schenk_AFE/af_shell6
Description: Olaf Schenk, Univ. Basel: AutoForm Eng. GmbH, Zurich. sheet metal forming. indefinite
![]() |
| (undirected graph drawing) |
![]() |
| Matrix properties | |
| number of rows | 504,855 |
| number of columns | 504,855 |
| nonzeros | 17,579,155 |
| structural full rank? | yes |
| structural rank | 504,855 |
| # of blocks from dmperm | 1 |
| # strongly connected comp. | 1 |
| explicit zero entries | 9,720 |
| nonzero pattern symmetry | symmetric |
| numeric value symmetry | symmetric |
| type | real |
| structure | symmetric |
| Cholesky candidate? | yes |
| positive definite? | no |
| author | AutoForm Eng. |
| editor | O. Schenk |
| date | 2003 |
| kind | subsequent structural problem |
| 2D/3D problem? | yes |
| Additional fields | size and type |
| b | full 504855-by-1 |
Notes:
next: Schenk_AFE/af_shell7 first: Schenk_AFE/af_shell1
| Ordering statistics: | result |
| nnz(chol(P*(A+A'+s*I)*P')) with AMD | 103,109,384 |
| Cholesky flop count | 6.8e+10 |
| nnz(L+U), no partial pivoting, with AMD | 205,713,913 |
| nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD | 211,044,595 |
| nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD | 411,101,115 |
Note that all matrix statistics (except nonzero pattern symmetry) exclude the 9720 explicit zero entries.
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.