Matrix properties
number of rows	2,987,012
number of columns	2,987,012
nonzeros	26,621,983
structural full rank?	yes
structural rank	2,987,012
# of blocks from dmperm	35
# strongly connected comp.	35
explicit zero entries	7
nonzero pattern symmetry	100%
numeric value symmetry	1%
type	real
structure	unsymmetric
Cholesky candidate?	no
positive definite?	no

author	K. Gullapalli
editor	T. Davis
date	2011
kind	circuit simulation problem
2D/3D problem?	no

Notes:

Full-chip circuit simulation matrix from Kiran Gullapalli, Freescale  
Semiconductor, Inc.                                                   
                                                                      
This is a full-chip (everything that is actually built in silicon is  
in the netlist), for an automotive part.  For simulation, the         
flash-memory and sram-memory cores are removed. But everything else is
in the matrix.                                                        
                                                                      
The chip takes an external battery (voltage source), but has internal 
voltage generators. the node of the external battery can be removed   
from the matrix. but the internal generators create some VERY HIGH    
degree nodes. So, there are about 6 nodes with degree greater than    
1000 (actually, the degree is 2M+ for 2 of these).                    
                                                                      
After ordering, nnz(L+U) = 200,180,468, with about 1.03793E+11        
flops (a += b * c is counted as one flop).                            

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	231,950,650
Cholesky flop count	1.0e+12
nnz(L+U), no partial pivoting, with AMD	460,914,288
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	1925080767262
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	4412417792620

Note that all matrix statistics (except nonzero pattern symmetry) exclude the 7 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.