TSEARCH
Replacing MATLAB's TSEARCH() Function


TSEARCH is a MATLAB library which compares several replacements for MATLAB's obsolete tsearch() function, which searched a Delaunay triangulation to find the triangle that encloses a given point.

Given a set of points P, it is possible to compute the Delaunay triangulation D(P), and then to very efficiently answer the question, what triangle T in D(P) contains a query point Q?

In earlier versions of MATLAB, this could be done by the following calls:

        d = delaunay ( px, py );
        t = tsearch ( px, py, d, qx, qy ); 
      

A MATLAB function mytsearch() was written, which allows the user to supply an initial guess for the triangle; if the guess is incorrect, then tsearch() is called to find the correct answer.

        d = delaunay ( px, py );
        t = guess values;
        t = tsearch_mex ( px, py, d, qx, qy, t ); 
      

A C function has been made available, which follows MATLAB's MEX interface standards, and which can also be used for this computation:

        d = delaunay ( px, py );
        t = tsearch_mex ( px, py, d, qx, qy ); 
      

But now tsearch() has been deleted, and the recommended calls are:

        d = DelaunayTri ( p );
        t = PointLocation ( d, q); 
      

The main purpose of the files in this directory is to examine the behavior of these various options.

Licensing:

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

Languages:

TSEARCH is available in a MATLAB version.

Related Data and Programs:

MESH2D, a MATLAB library which can automatically create a triangular mesh for a given polygonal region, by Darren Engwirda.

TRIANGULATION, a MATLAB library which performs various operations on order 3 (linear) or order 6 (quadratic) triangulations, including searching a Delaunay triangulation to find which triangle contains a given point.

Source Code:

Examples and Tests:

You can go up one level to the MATLAB source codes.


Last modified on 19 October 2013.