| Pairwise {spatstat} | R Documentation |
Creates an instance of a pairwise interaction point process model which can then be fitted to point pattern data.
Pairwise(pot, name, par, parnames, printfun)
pot |
An S language function giving the user-supplied pairwise interaction potential. |
name |
Character string. |
par |
List of numerical values for irregular parameters |
parnames |
Vector of names of irregular parameters |
printfun |
Do not specify this argument: for internal use only. |
Advanced use only.
This code constructs a member of the
pairwise interaction family pairwise.family
with arbitrary pairwise interaction potential given by
the user.
The function pot must take as its first argument
a matrix of interpoint distances, and evaluate the
potential for each of these distances. The result must be
either a matrix with the same dimensions as its input,
or an array with its first two dimensions the same as its input
(the latter case corresponds to a vector-valued potential).
If irregular parameters are present, then the second argument
to pot should be a vector of the same type as par
giving those parameter values.
An object of class "interact"
describing the interpoint interaction
structure of a point process.
Adrian Baddeley adrian@maths.uwa.edu.au http://www.maths.uwa.edu.au/~adrian/ and Rolf Turner rolf@math.unb.ca http://www.math.unb.ca/~rolf
ppm,
pairwise.family,
ppm.object
#This is the same as StraussHard(r=0.7,h=0.2)
strpot <- function(d,par) {
r <- par$r
h <- par$h
value <- (d <= r)
value[d < h] <- -Inf
value
}
mySH <- Pairwise(strpot, "StraussHard", list(r=0.7,h=0.2),
c("interaction distance r", "hard core distance c"))
data(cells)
ppm(cells, ~ 1, mySH)