Matrix properties
number of rows	22,695
number of columns	22,695
nonzeros	1,350,309
structural full rank?	yes
structural rank	22,695
# of blocks from dmperm	2
# strongly connected comp.	2
explicit zero entries	0
nonzero pattern symmetry	symmetric
numeric value symmetry	symmetric
type	binary
structure	symmetric
Cholesky candidate?	yes
positive definite?	no

author	B. Li
editor	T. Davis
date	1999
kind	duplicate electromagnetics problem
2D/3D problem?	yes

Notes:

nonzero pattern of Li/li

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	30,408,095
Cholesky flop count	7.9e+10
nnz(L+U), no partial pivoting, with AMD	60,793,495
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	28,808,169
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	49,884,385

SVD-based statistics:
norm(A)	83.7389
min(svd(A))	1.86805e-21
cond(A)	4.48269e+22
rank(A)	22,131
sprank(A)-rank(A)	564
null space dimension	564
full numerical rank?	no
singular value gap	195.457

singular values (MAT file):	click here
SVD method used:	s = svd (full (R)) ; where [~,R,E] = spqr (A) with droptol of zero
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.