Matrix properties
number of rows	3,024
number of columns	3,024
nonzeros	79,848
structural full rank?	no
structural rank	2,996
# of blocks from dmperm	3
# strongly connected comp.	29
explicit zero entries	0
nonzero pattern symmetry	symmetric
numeric value symmetry	symmetric
type	binary
structure	symmetric
Cholesky candidate?	no
positive definite?	no

author	A. Donovan
editor	I. Duff, R. Grimes, J. Lewis
date	1980
kind	structural problem
2D/3D problem?	yes

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	115,242
Cholesky flop count	5.7e+06
nnz(L+U), no partial pivoting, with AMD	227,460
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	167,244
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	431,610

SVD-based statistics:
norm(A)	31.6757
min(svd(A))	1.47521e-98
cond(A)	2.14721e+99
rank(A)	1,411
sprank(A)-rank(A)	1,585
null space dimension	1,613
full numerical rank?	no
singular value gap	6.11575e+10

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.