Matrix: Norris/stomach
Description: S.Norris, Univ. Auckland. 3D electro-physical model of a duodenum
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| (bipartite graph drawing) | (graph drawing of A+A') |
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| Matrix properties | |
| number of rows | 213,360 |
| number of columns | 213,360 |
| nonzeros | 3,021,648 |
| structural full rank? | yes |
| structural rank | 213,360 |
| # of blocks from dmperm | 1 |
| # strongly connected comp. | 1 |
| explicit zero entries | 0 |
| nonzero pattern symmetry | 85% |
| numeric value symmetry | 0% |
| type | real |
| structure | unsymmetric |
| Cholesky candidate? | no |
| positive definite? | no |
| author | S. Norris |
| editor | T. Davis |
| date | 2003 |
| kind | 2D/3D problem |
| 2D/3D problem? | yes |
| Ordering statistics: | result |
| nnz(chol(P*(A+A'+s*I)*P')) with AMD | 57,474,334 |
| Cholesky flop count | 5.1e+10 |
| nnz(L+U), no partial pivoting, with AMD | 114,735,308 |
| nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD | 110,927,497 |
| nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD | 205,340,721 |
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.