Matrix: ND/nd3k
Description: ND problem set, matrix nd3k
(undirected graph drawing) |
Matrix properties | |
number of rows | 9,000 |
number of columns | 9,000 |
nonzeros | 3,279,690 |
structural full rank? | yes |
structural rank | 9,000 |
# of blocks from dmperm | 1 |
# strongly connected comp. | 1 |
explicit zero entries | 0 |
nonzero pattern symmetry | symmetric |
numeric value symmetry | symmetric |
type | real |
structure | symmetric |
Cholesky candidate? | yes |
positive definite? | yes |
author | author unknown |
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 | 15,894,180 |
Cholesky flop count | 3.7e+10 |
nnz(L+U), no partial pivoting, with AMD | 31,779,360 |
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD | 13,949,445 |
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD | 27,269,737 |
SVD-based statistics: | |
norm(A) | 127.6 |
min(svd(A)) | 8.1423e-06 |
cond(A) | 1.56713e+07 |
rank(A) | 9,000 |
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.