CMU Unstructured Mesh Suite

David R. O'Hallaron and Jonathan Richard Shewchuk
School of Computer Science
Carnegie Mellon University

SF Meshes

The SF meshes are a collection of partitioned unstructured 3D meshes of the San Fernando Valley in Southern California. The meshes were generated as part of the Quake project using the Archimedes tool chain. The meshes are described and characterized in detail in the following report:

Files available for downloading

Mesh # nodes # elements All files (.node, .ele, .part) .node files .ele files .part files (1-128 subdomains)
sf10 7,29435,025 1.7M .06M .7M 1 |2 |4 |8 |16 |32 |64 |128 (.1M each)
sf5 30,169151,173 7M .25M 3M 1 |2 |4 |8 |16 |32 |64 |128 (.45M each)
sf2 378,7472,067,739 100M 3M 43M 1 |2 |4 |8 |16 |32 |64 |128 (6M each)
sf1 2,461,69413,980,162 630M 20M 285M 1 |2 |4 |8 |16 |32 |64 |128 (40M each)

File formats

A mesh is represented with two ASCII files in the Triangle format. The .node file contains the nodes in the mesh and their geometric coordinates. The .ele file contains the linear tetrahedral elements that comprise the mesh, and the nodes that comprise the corners of each element.

The meshes are partitioned into disjoint sets of elements using a geometric recursive bisection algorithm due to Miller, Teng, Thurston, and Vavasis. Each partition is described by an ASCII .part file, which lists the mapping of elements to subdomains. The formats of all files are described below.

The partitioned meshes can be displayed, manipulated, and saved as encapsulated color Postscript files using the X Windows based Showme program, which is distributed freely with the CMU Triangle Delaunay-based mesh generator program via Netlib.

.node files

Blank lines and comments prefixed by `#' may be placed anywhere. Nodes are numbered consecutively starting from one.

Each SF .node file contains two integer boundary markers that are artifacts of the specific solver we used to simulate the Northridge earthquake. They should be ignored.

.ele files

Blank lines and comments prefixed by `#' may be placed anywhere.

The 3 attributes are floating-point material properties.

.part files

Elements and subdomains are numbered from one.

[count] accesses since March 1998.
Questions or comments? Contact Dave O'Hallaron at