Matrix properties
number of rows	1,374
number of columns	1,374
nonzeros	8,588
structural full rank?	yes
structural rank	1,374
# of blocks from dmperm	57
# strongly connected comp.	1
explicit zero entries	18
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	13,888
Cholesky flop count	2.2e+05
nnz(L+U), no partial pivoting, with AMD	26,402
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	34,806
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	76,396

Note that all matrix statistics (except nonzero pattern symmetry) exclude the 18 explicit zero entries.

SVD-based statistics:
norm(A)	1102.12
min(svd(A))	2.9585e-12
cond(A)	3.72526e+14
rank(A)	1,308
sprank(A)-rank(A)	66
null space dimension	66
full numerical rank?	no
singular value gap	5.69136

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.