Matrix properties
number of rows	19,779
number of columns	19,779
nonzeros	1,316,789
structural full rank?	yes
structural rank	19,779
# of blocks from dmperm	1
# strongly connected comp.	1
explicit zero entries	11,822
nonzero pattern symmetry	symmetric
numeric value symmetry	symmetric
type	real
structure	symmetric
Cholesky candidate?	yes
positive definite?	yes

author	A. Raefsky
editor	H. Simon
date	1993
kind	structural problem
2D/3D problem?	yes

Additional fields	size and type
b	full 19779-by-1

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	7,304,797
Cholesky flop count	5.3e+09
nnz(L+U), no partial pivoting, with AMD	14,589,815
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	10,855,761
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	21,141,725

Note that all matrix statistics (except nonzero pattern symmetry) exclude the 11822 explicit zero entries.

SVD-based statistics:
norm(A)	2.66694e+11
min(svd(A))	0.0085203
cond(A)	3.1301e+13
rank(A)	19,771
sprank(A)-rank(A)	8
null space dimension	8
full numerical rank?	no
singular value gap	1.10382

singular values (MAT file):	click here
SVD method used:	s = svd (full (R)) ; where [~,R,E] = spqr (A) with droptol of zero
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.