Matrix properties
number of rows	68,121
number of columns	68,121
nonzeros	5,377,761
structural full rank?	yes
structural rank	68,121
# of blocks from dmperm	1
# strongly connected comp.	1
explicit zero entries	0
nonzero pattern symmetry	30%
numeric value symmetry	0%
type	real
structure	unsymmetric
Cholesky candidate?	no
positive definite?	no

author	B. Muite
editor	T. Davis
date	2007
kind	structural problem
2D/3D problem?	yes

Notes:

Chebyshev integration matrix from Benson Muite, Oxford.  Details of the  
matrices can be found in a preprint at http://www.maths.ox.ac.uk/~muite  
entitled "A comparison of Chebyshev methods for solving fourth-order     
semilinear initial boundary value problems," June 2007.   These matrices 
are very ill-conditioned, partly because of the dense rows which are hard
to scale when coupled with the rest of the matrix.                       

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	22,994,095
Cholesky flop count	1.6e+10
nnz(L+U), no partial pivoting, with AMD	45,920,069
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	118,684,230
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	2,320,269,381

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.