| marktable {spatstat} | R Documentation |
Visit each point in a point pattern, find the neighbouring points, and compile a frequency table of the marks of these neighbour points.
marktable(X, R, exclude=TRUE)
X |
A marked point pattern.
An object of class "ppp".
|
R |
Neighbourhood radius. |
exclude |
Logical. If exclude=TRUE, the neighbours of a point
do not include the point itself. If exclude=FALSE,
a point belongs to its own neighbourhood.
|
This algorithm visits each point in the point pattern X,
inspects all the neighbouring points within a radius R of the current
point, and compiles a frequency table of the marks attached to the
neighbours.
The dataset X must be a multitype point pattern, that is,
marks(X) must be a factor.
The result is a two-dimensional contingency table with one row for
each point in the pattern, and one column for each possible mark
value. The [i,j] entry in the table gives the number of
neighbours of point i that have mark j.
To perform more complicated calculations on the neighbours of every
point, use markstat or applynbd.
A contingency table (object of class "table") with one row for
each point in X, and one column for each possible mark value.
Adrian Baddeley adrian@maths.uwa.edu.au http://www.maths.uwa.edu.au/~adrian/ and Rolf Turner r.turner@auckland.ac.nz
markstat,
applynbd,
Kcross,
ppp.object,
table
data(amacrine) marktable(amacrine, 0.1) marktable(amacrine, 0.1, exclude=FALSE)