Matrix properties
number of rows	67,458
number of columns	67,458
nonzeros	623,914
structural full rank?	yes
structural rank	67,458
# of blocks from dmperm	29
# strongly connected comp.	29
explicit zero entries	56
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	optimization problem
2D/3D problem?	no

Additional fields	size and type
b	full 67458-by-1

Notes:

Revised Nov 2006; relative eps changes to A, right-hand-side added.
Note that this matrix should have been placed in the Schenk_IBMNA/ 
directory when it was first added in August 2004, but moving it now
would disrupt exising users of the collection.                     

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	2,780,353
Cholesky flop count	1.5e+09
nnz(L+U), no partial pivoting, with AMD	5,493,248
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	208,094,871
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	273,333,941

Note that all matrix statistics (except nonzero pattern symmetry) exclude the 56 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.