Matrix properties
number of rows	3,600
number of columns	3,600
nonzeros	26,600
structural full rank?	yes
structural rank	3,600
# of blocks from dmperm	2
# strongly connected comp.	2
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	1984
kind	structural problem
2D/3D problem?	yes

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	90,684
Cholesky flop count	4.2e+06
nnz(L+U), no partial pivoting, with AMD	177,768
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	159,993
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	295,488

SVD-based statistics:
norm(A)	1.27314e+08
min(svd(A))	7.21415
cond(A)	1.76478e+07
rank(A)	3,600
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.