<html lang="en"> <head> <title>Plotting the Triangulation - Untitled</title> <meta http-equiv="Content-Type" content="text/html"> <meta name="description" content="Untitled"> <meta name="generator" content="makeinfo 4.13"> <link title="Top" rel="start" href="index.html#Top"> <link rel="up" href="Delaunay-Triangulation.html#Delaunay-Triangulation" title="Delaunay Triangulation"> <link rel="next" href="Identifying-points-in-Triangulation.html#Identifying-points-in-Triangulation" title="Identifying points in Triangulation"> <link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage"> <meta http-equiv="Content-Style-Type" content="text/css"> <style type="text/css"><!-- pre.display { font-family:inherit } pre.format { font-family:inherit } pre.smalldisplay { font-family:inherit; font-size:smaller } pre.smallformat { font-family:inherit; font-size:smaller } pre.smallexample { font-size:smaller } pre.smalllisp { font-size:smaller } span.sc { font-variant:small-caps } span.roman { font-family:serif; font-weight:normal; } span.sansserif { font-family:sans-serif; font-weight:normal; } --></style> </head> <body> <div class="node"> <a name="Plotting-the-Triangulation"></a> <p> Next: <a rel="next" accesskey="n" href="Identifying-points-in-Triangulation.html#Identifying-points-in-Triangulation">Identifying points in Triangulation</a>, Up: <a rel="up" accesskey="u" href="Delaunay-Triangulation.html#Delaunay-Triangulation">Delaunay Triangulation</a> <hr> </div> <h4 class="subsection">29.1.1 Plotting the Triangulation</h4> <p>Octave has the functions <code>triplot</code> and <code>trimesh</code> to plot the Delaunay triangulation of a 2-dimensional set of points. <!-- ./geometry/triplot.m --> <p><a name="doc_002dtriplot"></a> <div class="defun"> — Function File: <b>triplot</b> (<var>tri, x, y</var>)<var><a name="index-triplot-2090"></a></var><br> — Function File: <b>triplot</b> (<var>tri, x, y, linespec</var>)<var><a name="index-triplot-2091"></a></var><br> — Function File: <var>h</var> = <b>triplot</b> (<var><small class="dots">...</small></var>)<var><a name="index-triplot-2092"></a></var><br> <blockquote><p>Plot a triangular mesh in 2D. The variable <var>tri</var> is the triangular meshing of the points <code>(</code><var>x</var><code>, </code><var>y</var><code>)</code> which is returned from <code>delaunay</code>. If given, the <var>linespec</var> determines the properties to use for the lines. The output argument <var>h</var> is the graphic handle to the plot. <!-- Texinfo @sp should work but in practice produces ugly results for HTML. --> <!-- A simple blank line produces the correct behavior. --> <!-- @sp 1 --> <p class="noindent"><strong>See also:</strong> <a href="doc_002dplot.html#doc_002dplot">plot</a>, <a href="doc_002dtrimesh.html#doc_002dtrimesh">trimesh</a>, <a href="doc_002ddelaunay.html#doc_002ddelaunay">delaunay</a>. </p></blockquote></div> <!-- ./geometry/trimesh.m --> <p><a name="doc_002dtrimesh"></a> <div class="defun"> — Function File: <b>trimesh</b> (<var>tri, x, y, z</var>)<var><a name="index-trimesh-2093"></a></var><br> — Function File: <var>h</var> = <b>trimesh</b> (<var><small class="dots">...</small></var>)<var><a name="index-trimesh-2094"></a></var><br> <blockquote><p>Plot a triangular mesh in 3D. The variable <var>tri</var> is the triangular meshing of the points <code>(</code><var>x</var><code>, </code><var>y</var><code>)</code> which is returned from <code>delaunay</code>. The variable <var>z</var> is value at the point <code>(</code><var>x</var><code>, </code><var>y</var><code>)</code>. The output argument <var>h</var> is the graphic handle to the plot. <!-- Texinfo @sp should work but in practice produces ugly results for HTML. --> <!-- A simple blank line produces the correct behavior. --> <!-- @sp 1 --> <p class="noindent"><strong>See also:</strong> <a href="doc_002dtriplot.html#doc_002dtriplot">triplot</a>, <a href="doc_002ddelaunay3.html#doc_002ddelaunay3">delaunay3</a>. </p></blockquote></div> <p>The difference between <code>triplot</code> and <code>trimesh</code> is that the former only plots the 2-dimensional triangulation itself, whereas the second plots the value of some function <code>f (</code><var>x</var><code>, </code><var>y</var><code>)</code>. An example of the use of the <code>triplot</code> function is <pre class="example"> rand ("state", 2) x = rand (20, 1); y = rand (20, 1); tri = delaunay (x, y); triplot (tri, x, y); </pre> <p>that plot the Delaunay triangulation of a set of random points in 2-dimensions. </body></html>