MATLAB Mathematics - SERC - Index of

2 Polynomials and Interpolation
Convex Hulls
The convhull function returns the indices of the points in a data set that
comprise the convex hull for the set. Use the plot function to plot the output of
convhull.
This example loads the seamount data and plots the longitudinal (x) and
latitudinal (y) data as a scatter plot. It then generates the convex hull and uses
plot to plot the convex hull:
load seamount
plot(x,y,'.','markersize',10)
k = convhull(x,y);
hold on, plot(x(k),y(k),'-r'), hold off
grid on
−47.95
−48
−48.05
−48.1
−48.15
−48.2
−48.25
−48.3
−48.35
−48.4
−48.45
210.8 211 211.2 211.4 211.6 211.8
Delaunay Triangulation
Given a set of coplanar data points, Delaunay triangulation is a set of lines
connecting each point to its natural neighbors. The delaunay function returns
a Delaunay triangulation as a set of triangles having the property that, for each
triangle, the unique circle circumscribed about the triangle contains no data
points.
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