dirichlet {spatstat.geom} | R Documentation |
Dirichlet Tessellation of Point Pattern
Description
Computes the Dirichlet tessellation of a spatial point pattern. Also known as the Voronoi or Thiessen tessellation.
Usage
dirichlet(X)
Arguments
X |
Spatial point pattern (object of class |
Details
In a spatial point pattern X
, the Dirichlet tile associated
with a particular point X[i]
is the region of space that is
closer to X[i]
than to any other point in X
. The
Dirichlet tiles divide the two-dimensional plane into disjoint
regions, forming a tessellation.
The Dirichlet tessellation is also known as the Voronoi or Thiessen tessellation.
This function computes the Dirichlet tessellation (within the original
window of X
) using the function deldir
in the package deldir.
To ensure that there is a one-to-one correspondence between the
points of X
and the tiles of dirichlet(X)
,
duplicated points in X
should first be removed by
X <- unique(X, rule="deldir")
.
The tiles of the tessellation will be computed as polygons if the original window is a rectangle or a polygon. Otherwise the tiles will be computed as binary masks.
Value
A tessellation (object of class "tess"
).
Author(s)
Adrian Baddeley Adrian.Baddeley@curtin.edu.au and Rolf Turner rolfturner@posteo.net.
See Also
tess
,
delaunay
,
ppp
,
dirichletVertices
.
For the Dirichlet tessellation on a linear network,
see lineardirichlet
.
Examples
X <- runifrect(42)
plot(dirichlet(X))
plot(X, add=TRUE)