Public Domain Software

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 dissections
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.