Matrix properties
number of rows	22,692
number of columns	22,692
nonzeros	1,482,390
structural full rank?	yes
structural rank	22,692
# 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	0%
type	complex
structure	symmetric
Cholesky candidate?	no
positive definite?	no

author	K. Meerbergen
editor	E. Rudnyi
date	2004
kind	model reduction problem
2D/3D problem?	yes

Additional fields	size and type
M	sparse 22692-by-22692
B	sparse 22692-by-1

Notes:

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

Ordering statistics:	AMD	METIS
nnz(chol(P*(A+A'+s*I)*P'))	8,698,416	6,019,098
Cholesky flop count	5.5e+09	2.3e+09
nnz(L+U), no partial pivoting	17,374,140	12,015,504
nnz(V) for QR, upper bound nnz(L) for LU	7,724,103	8,280,672
nnz(R) for QR, upper bound nnz(U) for LU	15,373,257	15,849,384

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.