Matrix properties
number of rows	2,919
number of columns	2,919
nonzeros	321,543
structural full rank?	no
structural rank	2,859
# of blocks from dmperm	3
# strongly connected comp.	61
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	342,009
Cholesky flop count	4.9e+07
nnz(L+U), no partial pivoting, with AMD	681,099
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	518,202
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	1,257,876

SVD-based statistics:
norm(A)	136.839
min(svd(A))	0
cond(A)	Inf
rank(A)	444
sprank(A)-rank(A)	2,415
null space dimension	2,475
full numerical rank?	no
singular value gap	5.04883e+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.