Matrix properties
number of rows	48
number of columns	48
nonzeros	24
structural full rank?	no
structural rank	24
# of blocks from dmperm	26
# strongly connected comp.	48
explicit zero entries	24
nonzero pattern symmetry	symmetric
numeric value symmetry	symmetric
type	integer
structure	symmetric
Cholesky candidate?	no
positive definite?	no

author	J. Lewis
editor	I. Duff, R. Grimes, J. Lewis
date	1982
kind	structural problem
2D/3D problem?	yes

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	48
Cholesky flop count	4.8e+01
nnz(L+U), no partial pivoting, with AMD	48
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	48
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	48

Note that all matrix statistics (except nonzero pattern symmetry) exclude the 24 explicit zero entries.

SVD-based statistics:
norm(A)	200
min(svd(A))	0
cond(A)	Inf
rank(A)	24
sprank(A)-rank(A)	0
null space dimension	24
full numerical rank?	no
singular value gap	Inf

singular values (MAT file):	click here
SVD method used:	s = sort (abs(full(diag(A))),'descend') ; since A is diagonal
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.