Matrix properties
number of rows	4,929
number of columns	4,929
nonzeros	33,108
structural full rank?	yes
structural rank	4,929
# of blocks from dmperm	352
# strongly connected comp.	2
explicit zero entries	77
nonzero pattern symmetry	0%
numeric value symmetry	0%
type	real
structure	unsymmetric
Cholesky candidate?	no
positive definite?	no

author	R. Burchett
editor	I. Duff, R. Grimes, J. Lewis
date	1984
kind	power network problem sequence
2D/3D problem?	no

Notes:

next: HB/gemat12 first: HB/gemat11

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	3,305,445
Cholesky flop count	5.3e+09
nnz(L+U), no partial pivoting, with AMD	6,605,961
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	42,976
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	88,390

Note that all matrix statistics (except nonzero pattern symmetry) exclude the 77 explicit zero entries.

SVD-based statistics:
norm(A)	692.75
min(svd(A))	1.16319e-05
cond(A)	5.95562e+07
rank(A)	4,929
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.