Matrix: HB/bcsstk01
Description: SYMMETRIC STIFFNESS MATRIX SMALL GENERALIZED EIGENVALUE PROBLEM
(undirected graph drawing) |
Matrix properties | |
number of rows | 48 |
number of columns | 48 |
nonzeros | 400 |
structural full rank? | yes |
structural rank | 48 |
# 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 | J. Lewis |
editor | I. Duff, R. Grimes, J. Lewis |
date | 1982 |
kind | structural problem |
2D/3D problem? | yes |
Ordering statistics: | result |
nnz(chol(P*(A+A'+s*I)*P')) with AMD | 489 |
Cholesky flop count | 6.0e+03 |
nnz(L+U), no partial pivoting, with AMD | 930 |
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD | 651 |
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD | 944 |
SVD-based statistics: | |
norm(A) | 3.01518e+09 |
min(svd(A)) | 3417.27 |
cond(A) | 882336 |
rank(A) | 48 |
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.