Matrix properties
number of rows	655
number of columns	655
nonzeros	2,808
structural full rank?	yes
structural rank	655
# of blocks from dmperm	198
# strongly connected comp.	2
explicit zero entries	46
nonzero pattern symmetry	1%
numeric value symmetry	0%
type	real
structure	unsymmetric
Cholesky candidate?	no
positive definite?	no

author	A. Westerberg
editor	I. Duff, R. Grimes, J. Lewis
date	1983
kind	chemical process simulation problem
2D/3D problem?	no

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	32,584
Cholesky flop count	4.0e+06
nnz(L+U), no partial pivoting, with AMD	64,513
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	6,358
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	12,688

Note that all matrix statistics (except nonzero pattern symmetry) exclude the 46 explicit zero entries.

SVD-based statistics:
norm(A)	318952
min(svd(A))	9.77241e-07
cond(A)	3.2638e+11
rank(A)	655
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 (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.