Areas of Morphological Dilations
Computes the areas of successive morphological dilations.
dilated.areas(X, r, W=NULL, ..., exact = FALSE)
- Object to be dilated.
A point pattern (object of class
"ppp"), a line segment pattern (object of class
"psp"), or a window (object of class
- Numeric vector of radii for the dilations.
- Optional. Window (object of class
"owin") inside which the areas will be computed, or
NULLindicating the entire area should be computed.
- Logical flag indicating whether areas should be computed
using analytic geometry (which is slower but more accurate).
Currently available only when
Xis a point pattern.
This function computes the areas of the dilations of
by each of the radii
r[i]. Areas may also be computed
inside a specified window
The morphological dilation of a set $X$ by a distance $r > 0$ is the subset consisting of all points $x$ such that the distance from $x$ to $X$ is less than or equal to $r$.
X is a point pattern, the dilation by a distance
$r$ is the union of
discs of radius $r$ centred at the points of
r should be a vector of nonnegative numbers.
exact=TRUE and if
X is a point pattern,
then the areas are computed using analytic geometry, which is
slower but much more accurate. Otherwise the computation is performed
To compute the dilated object itself, use
X <- runifpoint(10) a <- dilated.areas(X, c(0.1,0.2), W=square(1), exact=TRUE)