Matrix properties
number of rows	666
number of columns	666
nonzeros	4,032
structural full rank?	yes
structural rank	666
# of blocks from dmperm	41
# strongly connected comp.	1
explicit zero entries	12
nonzero pattern symmetry	82%
numeric value symmetry	59%
type	real
structure	unsymmetric
Cholesky candidate?	no
positive definite?	no

author	National Nuclear Corp.
editor	I. Duff, R. Grimes, J. Lewis
date	1982
kind	2D/3D problem
2D/3D problem?	yes

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	5,786
Cholesky flop count	6.7e+04
nnz(L+U), no partial pivoting, with AMD	10,906
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	12,485
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	26,064

Note that all matrix statistics (except nonzero pattern symmetry) exclude the 12 explicit zero entries.

SVD-based statistics:
norm(A)	1086.07
min(svd(A))	5.31325e-08
cond(A)	2.04409e+10
rank(A)	666
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.