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
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:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	113,825
Cholesky flop count	3.6e+06
nnz(L+U), no partial pivoting, with AMD	221,631
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	65,968
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	135,773

SVD-based statistics:
norm(A)	4.38971
min(svd(A))	5.97432e-18
cond(A)	7.34763e+17
rank(A)	6,018
sprank(A)-rank(A)	1
null space dimension	1
full numerical rank?	no
singular value gap	6.4482e+11

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.