Matrix properties
number of rows	17,361
number of columns	17,361
nonzeros	1,021,159
structural full rank?	yes
structural rank	17,361
# of blocks from dmperm	1
# strongly connected comp.	1
explicit zero entries	0
nonzero pattern symmetry	symmetric
numeric value symmetry	symmetric
type	real
structure	symmetric
Cholesky candidate?	yes
positive definite?	yes

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

Additional fields	size and type
M	sparse 17361-by-17361
B	sparse 17361-by-1
C	sparse 12-by-17361
cname	full 12-by-7

Notes:

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

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	1,232,355
Cholesky flop count	1.2e+08
nnz(L+U), no partial pivoting, with AMD	2,447,349
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	3,282,796
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	10,285,290

SVD-based statistics:
norm(A)	3.65695e+09
min(svd(A))	3.33715
cond(A)	1.09583e+09
rank(A)	17,361
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.