Matrix properties
number of rows	20,082
number of columns	20,082
nonzeros	281,150
structural full rank?	yes
structural rank	20,082
# 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	87%
type	real
structure	unsymmetric
Cholesky candidate?	no
positive definite?	no

author	C. Moosmann, A. Griener
editor	E. Rudnyi
date	2004
kind	model reduction problem
2D/3D problem?	yes

Additional fields	size and type
E	sparse 20082-by-20082
B	sparse 20082-by-1
C	sparse 5-by-20082
cname	full 5-by-6

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'))	6,111,848	3,834,303
Cholesky flop count	5.0e+09	1.7e+09
nnz(L+U), no partial pivoting	12,203,614	7,648,524
nnz(V) for QR, upper bound nnz(L) for LU	8,897,575	6,945,975
nnz(R) for QR, upper bound nnz(U) for LU	16,070,062	12,965,671

Maintained by Tim Davis, last updated 30-Sep-2008.
Matrix pictures by cspy, a MATLAB function in the CSparse package.
Matrix graphs by Yifan Hu, AT&T Labs Visualization Group.