Matrix: JGD_BIBD/bibd_16_8
Description: Balanced Incomplete Block Design from Mark Giesbrecht, Univ. of Waterloo
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| (bipartite graph drawing) |
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| Matrix properties | |
| number of rows | 120 |
| number of columns | 12,870 |
| nonzeros | 360,360 |
| structural full rank? | yes |
| structural rank | 120 |
| # of blocks from dmperm | 1 |
| # strongly connected comp. | 1 |
| explicit zero entries | 0 |
| nonzero pattern symmetry | 0% |
| numeric value symmetry | 0% |
| type | binary |
| structure | rectangular |
| Cholesky candidate? | no |
| positive definite? | no |
| author | M. Giesbrecht |
| editor | J.-G. Dumas |
| date | 2008 |
| kind | combinatorial problem |
| 2D/3D problem? | no |
Notes:
Balanced Incomplete Block Design from Mark Giesbrecht, Univ. of Waterloo
From Jean-Guillaume Dumas' Sparse Integer Matrix Collection,
http://ljk.imag.fr/membres/Jean-Guillaume.Dumas/simc.html
Filename in JGD collection: BIBD/bibd_16_8_120x12870.sms
| Ordering statistics: | result |
| nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD | 1,362,228 |
| nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD | 7,260 |
| SVD-based statistics: | |
| norm(A) | 289.972 |
| min(svd(A)) | 30.3974 |
| cond(A) | 9.53939 |
| rank(A) | 120 |
| 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.