Matrix properties
number of rows	20,000
number of columns	20,000
nonzeros	45,000
structural full rank?	yes
structural rank	20,000
# of blocks from dmperm	5,000
# strongly connected comp.	5,000
explicit zero entries	0
nonzero pattern symmetry	symmetric
numeric value symmetry	symmetric
type	real
structure	symmetric
Cholesky candidate?	no
positive definite?	no

author	N. Gould
editor	N. Gould
date	1999
kind	optimization problem
2D/3D problem?	no

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	35,000
Cholesky flop count	6.5e+04
nnz(L+U), no partial pivoting, with AMD	50,000
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	40,000
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	50,000

SVD-based statistics:
norm(A)	2.76911
min(svd(A))	0.430214
cond(A)	6.43658
rank(A)	20,000
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 (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.