Circuit simulation matrix from Raj
Name Raj1
Group Rajat
Matrix ID 1863
Num Rows 263,743
Num Cols 263,743
Nonzeros 1,300,261
Pattern Entries 1,302,464
Kind Circuit Simulation Problem
Symmetric No
Date 2007
Author Raj
Editor T. Davis
Structural Rank 263,743
Structural Rank Full true
Num Dmperm Blocks 169
Strongly Connect Components 3
Num Explicit Zeros 2,203
Pattern Symmetry 99.9%
Numeric Symmetry 57.6%
Cholesky Candidate no
Positive Definite no
Type real
Download MATLAB Rutherford Boeing Matrix Market
High fill-in with KLU, because the matrix is nearly singular and lots of 
partial pivoting occurs.  If the pattern of A+A' is considered to be the 
nonzero pattern of a symmetric positive definite matrix, then nnz(L) has 
only 3,728,967 nonzeros using p=amd(A) and chol(A(p,p)), where A excludes
the explicit zeros in Problem.Zeros.  The flop count for the Cholesky    
factorization is only 340.9 million.  With a pivot tolerance of 2.2e-16, 
KLU Version 1.0 constructs and LU factorization with about 31 million    
nonzeros, even though it uses AMD for the diagonal blocks of the BTF for 
which the expected nnz(L) is only 3.705 million (for the Cholesky factor-
ization of the large diagonal block).  The BTF form has little impact on 
the factorization.