Matrix properties
number of rows	1,668
number of columns	1,668
nonzeros	10,750
structural full rank?	yes
structural rank	1,668
# of blocks from dmperm	1
# strongly connected comp.	1
entries not in dmperm blocks	0
explicit zero entries	0
nonzero pattern symmetry	symmetric
numeric value symmetry	symmetric
type	real
structure	symmetric
Cholesky candidate?	no
positive definite?	no

author	D. Hohlfield, T. Bechtold, H. Zappe
editor	E. Rudnyi
date	2006
kind	model reduction problem
2D/3D problem?	yes

Additional fields	size and type
E	sparse 1668-by-1668
B	sparse 1668-by-1
C	sparse 5-by-1668
cname	full 5-by-5

Notes:

Primary matrix in this model reduction problem is the Oberwolfach A matrix

Ordering statistics:	AMD	METIS
nnz(chol(P*(A+A'+s*I)*P'))	22,483	24,570
Cholesky flop count	5.8e+05	6.4e+05
nnz(L+U), no partial pivoting	43,298	47,472
nnz(V) for QR, upper bound nnz(L) for LU	35,461	36,907
nnz(R) for QR, upper bound nnz(U) for LU	65,784	68,586

Maintained by Tim Davis, last updated 04-May-2008.
Matrix pictures by cspy, a MATLAB function in the CSparse package.
Matrix graphs by Yifan Hu, AT&T Labs Visualization Group.