Matrix properties
number of rows	79,171
number of columns	79,171
nonzeros	4,352,105
structural full rank?	yes
structural rank	79,171
# 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?	no
positive definite?	no

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

Additional fields	size and type
E	sparse 79171-by-79171
B	sparse 79171-by-1
C	sparse 7-by-79171
cname	full 7-by-7

Notes:

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

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	125,237,918
Cholesky flop count	5.2e+11
nnz(L+U), no partial pivoting, with AMD	250,396,665
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	191,253,531
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	388,699,872

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.