This toolbox contains Matlab code for several graph and mesh partitioning
methods, including geometric, spectral, geometric spectral, and coordinate
bisection.  It also has routines to generate recursive multiway partitions, 
vertex separators, and nested dissection orderings; and it has some sample
meshes and mesh generators.  

The toolbox contains a Matlab interface to Leland and Hendrickson's 
Chaco partitioning package, but it doesn't contain Chaco itself.  
The file "chaco/README" tells how to install the interface to Chaco.
It also contains a Matlab interface to Karypis et al.'s Metis
partitioning package, using Robert Bridson's "metismex" code.

Demonstrations.
  Say "meshdemo" for some examples.
  Also, many of the individual routines can draw pictures of what they do.

Partitioning methods.
  geopart        - Geometric. 
  specpart       - Spectral.
  gspart         - Geometric spectral.
  coordpart      - Coordinate bisection.
  inertpart      - Inertial bisection.
  chaco          - Multilevel Kernighan-Lin, and other options.
  metispart      - Multilevel method from Metis.
  metismex       - Interface to more options of Metis.

Multiway partitions.
  dice           - Use any 2-way partitioner to get a multiway partition.
  geodice        - Recursive geometric partitioning.
  specdice       - Recursive spectral partitioning.
  gsdice         - Recursive geometric spectral partitioning.
  chaco          - Can also produce multiway partitions directly.
  metisdice      - Multiway partitioning from Metis.

Vertex separators.
  vtxsep         - Convert a 2-way partition to a vertex separator.
  geosep         - Vertex separator from geometric partitioning.
  specsep        - Vertex separator from spectral partitioning.

Nested dissection.
  ndperm         - Use any 2-way partitioner for nested dissection.
  geond          - Geometric nested dissection ordering.
  specnd         - Spectral nested dissection ordering.
  gsnd           - Geometric spectral nested dissection ordering.
  metisnd        - Nested dissection ordering from Metis.
  analyze        - Predict fill, opcount, etc. for an elimination ordering.

Meshes and graph generators.
  meshes.mat     - Three sample meshes with coordinates:
    Eppstein     - A 2D finite-element mesh with 547 nodes.
    Smallmesh    - A 2D finite-element mesh with 136 nodes.
    Tapir        - A 2D finite-element mesh with 1024 nodes.
  grid5          - 2D square 5-point mesh.
  grid7          - 2D square 7-point mesh.
  grid9          - 2D square 9-point mesh.
  gridt          - 2D triangular mesh.
  grid3d         - 3D cubical mesh.
  grid3dt        - 3D cubical simplicial mesh.
  badmesh        - A mesh that has no good straight-line cut.
  cockroach      - A mesh for which spectral bisection does poorly.
  treexpath      - A mesh for which spectral bisection does poorly.

Visualization and graphics.
  (All the partitioners can also draw pictures of what they do.)
  gplotpart      - Draw a 2-way partition.
  gplotmap       - Draw a multiway partition.
  highlight      - Draw a mesh with some vertices highlighted.
  gplotg         - Draw a 2D or 3D mesh (replaces Matlab's gplot).
  etreeplotg     - Draw an elimination tree (replaces Matlab's etreeplot).
  spypart        - Matrix spy plot with partition boundaries.
  dmspy          - Spy plot of matrix in block triangular form.
 
Utilities.
  cutsize        - Find or count edges cut by a partition.
  other          - Other side of a partition, or change representations.
  intersection   - Intersection of two sets.
  union          - Union of two sets.
  fiedler        - Fiedler vector of a graph.
  laplacian      - Laplacian matrix of a graph.
  components     - Connected components of a graph.
  contract       - Condense a graph according to a given block structure.
  distances      - Distances between adjacent mesh points.
  blockdiags     - Create matrix with specified block diagonals.
  resetrandoms   - Reset random number generators to startup values.

References

  John R. Gilbert, Gary L. Miller, and Shang-Hua Teng.
  Geometric mesh partitioning:  Implementation and experiments.
  SIAM J. Scientific Computing 19:2091-2110, 1998.

  Tony F. Chan, John R. Gilbert, and Shang-Hua Teng.
  Geometric spectral partitioning.
  Xerox PARC Technical Report CSL-94-15, 1995.

  Bruce Hendrickson and Robert Leland.
  The Chaco user's guide, version 2.0.
  Sandia National Laboratories Technical Report SAND94-2692, 1994.

  George Karypis et al.
  METIS, Serial graph partitioning, version 4.0.1, November 1998.
  http://www.cs.umn.edu/~karypis/metis
  
  Robert Bridson.
  A MATLAB CMEX interface to the Metis library. 
  http://www.stanford.edu/~rbridson/download/metismex.c