Matrix properties
number of rows	381,381
number of columns	381,381
nonzeros	3,413,113
structural full rank?	yes
structural rank	381,381
# of blocks from dmperm	1
# strongly connected comp.	1
explicit zero entries	0
nonzero pattern symmetry	100%
numeric value symmetry	57%
type	complex
structure	unsymmetric
Cholesky candidate?	no
positive definite?	no

author	J. Washbourne
editor	T. Davis
date	2012
kind	2D/3D problem
2D/3D problem?	no

Notes:

Complex unsymmetric matrix arising from a 2D Helmholtz formulation
for temporal frequency domain seismic modeling.                   
From John Washbourne, Chevron                                     

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	29,586,698
Cholesky flop count	1.7e+10
nnz(L+U), no partial pivoting, with AMD	58,792,015
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	36,013,643
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	67,753,525

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.