15.11.2014 Views

MATLAB Mathematics - SERC - Index of

MATLAB Mathematics - SERC - Index of

MATLAB Mathematics - SERC - Index of

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

Interpolation<br />

Functions for Multidimensional Geometrical Analysis<br />

Function<br />

convhulln<br />

delaunayn<br />

dsearchn<br />

griddatan<br />

tsearchn<br />

voronoin<br />

Description<br />

N-dimensional convex hull.<br />

N-dimensional Delaunay tessellation.<br />

N-dimensional nearest point search.<br />

N-dimensional data gridding and hypersurface fitting.<br />

N-dimensional closest simplex search.<br />

N-dimensional Voronoi diagrams.<br />

This section demonstrates these geometric analysis techniques:<br />

• Convex hulls<br />

• Delaunay triangulations<br />

• Voronoi diagrams<br />

• Interpolation <strong>of</strong> scattered multidimensional data<br />

Convex Hulls<br />

The convex hull <strong>of</strong> a data set in n-dimensional space is defined as the smallest<br />

convex region that contains the data set.<br />

Computing a Convex Hull. The convhulln function returns the indices <strong>of</strong> the<br />

points in a data set that comprise the facets <strong>of</strong> the convex hull for the set. For<br />

example, suppose X is an 8-by-3 matrix that consists <strong>of</strong> the 8 vertices <strong>of</strong> a cube.<br />

The convex hull <strong>of</strong> X then consists <strong>of</strong> 12 facets:<br />

d = [-1 1];<br />

[x,y,z] = meshgrid(d,d,d);<br />

X = [x(:),y(:),z(:)];<br />

C = convhulln(X)<br />

% 8 corner points <strong>of</strong> a cube<br />

C =<br />

4 2 1<br />

3 4 1<br />

2-27

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!