circuitscape: circuit theory applied to animal/gene flow. B. McRae, UCSB
Name ecology1
Group McRae
Matrix ID 1882
Num Rows 1,000,000
Num Cols 1,000,000
Nonzeros 4,996,000
Pattern Entries 4,996,000
Kind 2D/3D Problem
Symmetric Yes
Date 2008
Author B. McRae
Editor T. Davis
Structural Rank 1,000,000
Structural Rank Full true
Num Dmperm Blocks 1
Strongly Connect Components 1
Num Explicit Zeros 0
Pattern Symmetry 100%
Numeric Symmetry 100%
Cholesky Candidate yes
Positive Definite no
Type real
Download MATLAB Rutherford Boeing Matrix Market
Landscape ecology problem, using electrical network theory to model 
animal movement an gene flow.  The McRae/ecology1 matrix comes from 
a 2D, 1000-by-1000 mesh (5 pt stencil).  It is an ill-conditioned   
symmetric indefinite matrix.  Source: Brad McRae, National Center   
for Ecological Analysis and Synthesis Santa Barbara, CA.