**triangulation_mask_test**,
a MATLAB code which
calls triangulation_mask(), which
reads the nodes and triangles that define a triangulation,
call a user routine which determines whether each triangle is to
be preserved or discarded ("masked") from the triangulation,
and write out new node and triangle files that define the
masked triangulation.

The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.

triangulation_mask, a MATLAB code which reads a triangulation and calls a user-supplied routine to consider each triangle for deletion;

- triangulation_mask_test.m, calls all the tests.
- triangulation_mask_test.sh, runs all the tests.
- triangulation_mask_test.txt, the output file.

**P15** is a triangulation created by calling DISTMESH,
then removing duplicate points by calling TABLE_MERGE,
then creating a Delaunay triangulation by calling TABLE_DELAUNAY,
Unfortunately, this results in many triangles that lie outside
the region of interest.

- p15_nodes.txt, a set of nodes.
- p15_nodes.png, a PNG image of the nodes.
- p15_elements.txt, a set of order 3 triangles.
- p15_elements.png, a PNG image of the elements.
- p15_mask.m, a routine which masks the triangles by dropping those whose centroids lie outside the region.
- p15_mask.txt, the output from a run of the program.
- p15_mask_nodes.txt, the nodes after masking.
- p15_mask_elements.txt, the elements after masking.
- p15_mask_elements.png, PNG image of the elements after masking.

**SMALL** is a triangulation of the 25 lattice points on
the [0,4]x[0,4] square. Our masking operation should cut out
a lower left triangular corner and a section from the upper right.

- small_nodes.txt, a set of nodes.
- small_nodes.png, an image of the original nodes.
- small_elements.txt, a set of order 3 triangles.
- small_elements.png, a PNG image of the original elements.
- small_mask.m, a routine which masks the triangles by dropping those whose centroids lie outside the region.
- small_mask.txt, the output from a run of the program.
- small_mask_nodes.txt, the set of nodes after masking.
- small_mask_nodes.png, an image of the nodes after masking.
- small_mask_elements.txt, the set of elements after masking.
- small_mask_elements.png, a PNG image of the elements after masking.