Matrix properties
number of rows	3,240
number of columns	3,240
nonzeros	3,240
structural full rank?	yes
structural rank	3,240
# of blocks from dmperm	3,240
# strongly connected comp.	3,240
explicit zero entries	0
nonzero pattern symmetry	symmetric
numeric value symmetry	symmetric
type	binary
structure	symmetric
Cholesky candidate?	yes
positive definite?	yes

author	M. Giesbrecht
editor	J.-G. Dumas
date	2008
kind	combinatorial problem
2D/3D problem?	no

Notes:

Balanced Incomplete Block Design from Mark Giesbrecht, Univ. of Waterloo
From Jean-Guillaume Dumas' Sparse Integer Matrix Collection,            
http://ljk.imag.fr/membres/Jean-Guillaume.Dumas/simc.html               
                                                                        
Filename in JGD collection: BIBD/bibd_81_2_3240x3240.sms                

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	3,240
Cholesky flop count	3.2e+03
nnz(L+U), no partial pivoting, with AMD	3,240
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	3,240
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	3,240

SVD-based statistics:
norm(A)	1
min(svd(A))	1
cond(A)	1
rank(A)	3,240
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.