Matrix properties
number of rows	40,216
number of columns	40,216
nonzeros	1,042,160
structural full rank?	yes
structural rank	40,216
# of blocks from dmperm	2
# strongly connected comp.	2
explicit zero entries	0
nonzero pattern symmetry	symmetric
numeric value symmetry	symmetric
type	real
structure	symmetric
Cholesky candidate?	no
positive definite?	no

author	J. Quanyuan
editor	T. Davis
date	2008
kind	power network problem sequence
2D/3D problem?	no

Additional fields	size and type
b	sparse 40216-by-1
A	cell 13-by-1
b1	cell 13-by-1
b2	cell 13-by-1

Notes:

Transient stabilty constrained interior pt. optimal power flow, J. Quanyuan
Two problem sets from Dr. Jiang Quanyuan from Zhejiang University,         
Hangzhou, China, March, 2008, used in an electrical power system.          
Each matrix A is solved sequentially with two right-hand-sides, b1 and     
b2, one at a time.  In the UF collection, the sequence of all first        
and second right-hand-sides is in Problem.aux.b2 and Problem.aux.b1.       
These matrices are symmetric indefinite (x=A\b uses MA57)                  
Note that the last matrices in the sequence are ill-conditioned.           
                                                                           
Transient Stability Constrained Interior Point Optimal Power Flow Program  
      Version 1.0 -- Developed by Dr. Jiang Quanyuan, March 2008           
                                                                           
case39.m - TSOPF converges after 13 iterations                             
 object    = 2.696268E+04                                                  
 max_equ   = 5.684342E-14                                                  
 low_inequ = -1.110223E-16                                                 
 up_inequ  = None                                                          

Ordering statistics:	result
nnz(chol(P*(A+A'+s*I)*P')) with AMD	2,913,459
Cholesky flop count	4.3e+08
nnz(L+U), no partial pivoting, with AMD	5,786,702
nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD	126,758,904
nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD	218,420,262

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.