Matrix properties
number of rows	6,019
number of columns	6,019
nonzeros	23,492
structural full rank?	yes
structural rank	6,019
# of blocks from dmperm	33
# strongly connected comp.	33
entries not in dmperm blocks	426
explicit zero entries	0
nonzero pattern symmetry	0%
numeric value symmetry	0%
type	binary
structure	unsymmetric
Cholesky candidate?	no
positive definite?	no

author	NASA
editor	G. Kumfert, A. Pothen
date	1995
kind	duplicate structural problem
2D/3D problem?	yes

Notes:

Let A=Nasa/barth4, then Pothen/barth4 = spones(A+A') with xyz coord.

Ordering statistics:	AMD	METIS	DMPERM+
nnz(chol(P*(A+A'+s*I)*P'))	113,825	121,894	110,109
Cholesky flop count	3.6e+06	4.2e+06	3.5e+06
nnz(L+U), no partial pivoting	221,631	237,769	214,625
nnz(V) for QR, upper bound nnz(L) for LU	65,968	74,515	65,717
nnz(R) for QR, upper bound nnz(U) for LU	135,773	142,108	126,763

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.