Matrix properties
number of rows	259,789
number of columns	259,789
nonzeros	4,242,673
structural full rank?	yes
structural rank	259,789
# of blocks from dmperm	1
# strongly connected comp.	1
explicit zero entries	0
nonzero pattern symmetry	symmetric
numeric value symmetry	symmetric
type	real
structure	symmetric
Cholesky candidate?	yes
positive definite?	yes

author	E. Um
editor	T. Davis
date	2010
kind	electromagnetics problem
2D/3D problem?	yes

Additional fields	size and type
b	full 259789-by-1

Notes:

This is a finite-element system matrix deriving from the 3D transient
electric field diffusion equation. The matrix results from the       
discretization of offshore conductivity structures using tetrahedral 
elements.  Evan Um, Geophysics, Stanford.                            

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	158,143,888
Cholesky flop count	4.6e+11
nnz(L+U), no partial pivoting, with AMD	316,027,987
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	392,939,742
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	744,604,111

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.