Matrix properties
number of rows	41,731
number of columns	41,731
nonzeros	559,339
structural full rank?	yes
structural rank	41,731
# of blocks from dmperm	3
# strongly connected comp.	3
explicit zero entries	4
nonzero pattern symmetry	symmetric
numeric value symmetry	symmetric
type	real
structure	symmetric
Cholesky candidate?	no
positive definite?	no

author	IBM
editor	O. Schenk
date	2004
kind	subsequent optimization problem
2D/3D problem?	no

Additional fields	size and type
b	full 41731-by-1

Notes:

next: - first: Schenk_IBMNA/c-62                                       
A version of this matrix was first obtained from Olaf Schenk in October
2003.  That version appears in this collection as Schenk_IBMNA/c-62.   
In August 2004, a new version appeared in the GHS collection, under the
same name, and was added here as GHS_indef/c-62ghs.  The c-62ghs matrix
is the same as the version on Schenk's web site as of Nov 2006, except 
that the right-hand-side was missing in the version in the UF Sparse   
Matrix Collection (now included).  The two matrices c-62 and c-62ghs   
are very similar, but not identical.                                   

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	9,819,875
Cholesky flop count	1.7e+10
nnz(L+U), no partial pivoting, with AMD	19,598,019
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	125,385,616
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	173,361,037

Note that all matrix statistics (except nonzero pattern symmetry) exclude the 4 explicit zero entries.

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.