Matrix: Bai/qh768
Description: QUEBEC HYDRO POWER SYSTEM
(bipartite graph drawing) | (graph drawing of A+A') |
Matrix properties | |
number of rows | 768 |
number of columns | 768 |
nonzeros | 2,934 |
structural full rank? | yes |
structural rank | 768 |
# of blocks from dmperm | 43 |
# strongly connected comp. | 1 |
explicit zero entries | 0 |
nonzero pattern symmetry | 93% |
numeric value symmetry | 0% |
type | real |
structure | unsymmetric |
Cholesky candidate? | no |
positive definite? | no |
author | D. Ndereyimana |
editor | Z. Bai, D. Day, J. Demmel, J. Dongarra |
date | 1994 |
kind | power network problem |
2D/3D problem? | no |
Ordering statistics: | result |
nnz(chol(P*(A+A'+s*I)*P')) with AMD | 2,884 |
Cholesky flop count | 1.2e+04 |
nnz(L+U), no partial pivoting, with AMD | 5,000 |
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD | 3,205 |
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD | 6,409 |
SVD-based statistics: | |
norm(A) | 1.3567e+13 |
min(svd(A)) | 0.000157026 |
cond(A) | 8.63998e+16 |
rank(A) | 644 |
sprank(A)-rank(A) | 124 |
null space dimension | 124 |
full numerical rank? | no |
singular value gap | 1.03685 |
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.