Matrix properties
number of rows	1,624
number of columns	1,624
nonzeros	6,050
structural full rank?	yes
structural rank	1,624
# of blocks from dmperm	1
# strongly connected comp.	1
explicit zero entries	0
nonzero pattern symmetry	symmetric
numeric value symmetry	symmetric
type	binary
structure	symmetric
Cholesky candidate?	yes
positive definite?	no

author	B. Dembart, J. Lewis
editor	I. Duff, R. Grimes, J. Lewis
date	1981
kind	power network problem
2D/3D problem?	no

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	5,623
Cholesky flop count	2.5e+04
nnz(L+U), no partial pivoting, with AMD	9,622
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	8,544
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	16,961

SVD-based statistics:
norm(A)	5.78591
min(svd(A))	3.44732e-17
cond(A)	1.67838e+17
rank(A)	1,613
sprank(A)-rank(A)	11
null space dimension	11
full numerical rank?	no
singular value gap	1.54455e+11

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.