Matrix properties
number of rows	25,710
number of columns	25,710
nonzeros	3,749,582
structural full rank?	yes
structural rank	25,710
# of blocks from dmperm	1
# strongly connected comp.	1
explicit zero entries	3,602
nonzero pattern symmetry	symmetric
numeric value symmetry	symmetric
type	real
structure	symmetric
Cholesky candidate?	yes
positive definite?	yes

author	R. Kouhia
editor	T. Davis
date	2008
kind	structural problem
2D/3D problem?	yes

Additional fields	size and type
b	full 25710-by-1
coord	full 25710-by-3

Notes:

Matrix problems from Reijo Kouhia, Structural Mechanics, Helsinki      
University of Technology.   http://users.tkk.fi/~kouhia/sparse.html    
                                                                       
Surface mount transistor, 1704 reduced triquadratic elem, therm stress.
This is a stiffness matrix from a thermal stress analysis of           
a surface mounted transistor.  Due to symmetry only one half of        
the model is discretized in 1704 standard reduced triquadratic elements
(20 node serendipity).  There are 5 different materials.               
The stiffness matrix is integrated by 3x3x3 Gaussian quadrature.       
Separate load vector file is also available.                           
Figure of the FE model can be seen in a separate description,          
or downloaded as a postscript file from the contributors www-pages.    
Contributor:                                                           
Reijo Kouhia, Helsinki University of Technology,                       
               Laboratory of Structural Mechanics                      
               PO Box 2100, 02015 HUT, Finland                         
 e-mail: reijo.kouhia@hut.fi                                           
 http://www.hut.fi/~kouhia                                             

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	14,601,688
Cholesky flop count	1.4e+10
nnz(L+U), no partial pivoting, with AMD	29,177,666
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	26,940,204
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	65,904,871

Note that all matrix statistics (except nonzero pattern symmetry) exclude the 3602 explicit zero entries.

SVD-based statistics:
norm(A)	5.29766e+06
min(svd(A))	0.00333867
cond(A)	1.58676e+09
rank(A)	25,710
sprank(A)-rank(A)	0
null space dimension	0
full numerical rank?	yes

singular values (MAT file):	click here
SVD method used:	s = svd (full (A))
status:	ok

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.