Matrix properties
number of rows	1,454
number of columns	1,454
nonzeros	5,300
structural full rank?	yes
structural rank	1,454
# 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	4,885
Cholesky flop count	2.0e+04
nnz(L+U), no partial pivoting, with AMD	8,316
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	7,217
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	14,093

SVD-based statistics:
norm(A)	5.61949
min(svd(A))	2.07095e-18
cond(A)	2.71348e+18
rank(A)	1,446
sprank(A)-rank(A)	8
null space dimension	8
full numerical rank?	no
singular value gap	6.47462e+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.