Matrix: HB/saylr1
Description: UNSYMMETRIC MATRIX OF PAUL SAYLOR - 14 BY 17 2D GRID MAY, 1983
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| Matrix properties | |
| number of rows | 238 |
| number of columns | 238 |
| nonzeros | 1,128 |
| structural full rank? | yes |
| structural rank | 238 |
| # of blocks from dmperm | 1 |
| # strongly connected comp. | 1 |
| explicit zero entries | 0 |
| nonzero pattern symmetry | symmetric |
| numeric value symmetry | 65% |
| type | real |
| structure | unsymmetric |
| Cholesky candidate? | no |
| positive definite? | no |
| author | R. Kendall, D. Peaceman, H. Stone, W. Watts |
| editor | P. Saylor |
| date | 1984 |
| kind | computational fluid dynamics problem |
| 2D/3D problem? | yes |
| Ordering statistics: | result |
| nnz(chol(P*(A+A'+s*I)*P')) with AMD | 1,908 |
| Cholesky flop count | 2.0e+04 |
| nnz(L+U), no partial pivoting, with AMD | 3,578 |
| nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD | 2,631 |
| nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD | 4,686 |
| SVD-based statistics: | |
| norm(A) | 4.83249e+08 |
| min(svd(A)) | 0.621097 |
| cond(A) | 7.78058e+08 |
| rank(A) | 238 |
| sprank(A)-rank(A) | 0 |
| null space dimension | 0 |
| full numerical rank? | yes |
| singular values (MAT file): | click here |
| SVD method used: | s = svd (full (A)) ; |
| status: | ok |

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.