Pairwise
Generic Pairwise Interaction model
Creates an instance of a pairwise interaction point process model which can then be fitted to point pattern data.
Usage
Pairwise(pot, name, par, parnames, printfun)Arguments
- 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.
Details
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.
Value
- An object of class
"interact"describing the interpoint interaction structure of a point process.
See Also
Examples
#This is the same as StraussHard(r=0.7,h=0.05)
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=0.05),
c("interaction distance r", "hard core distance c"))
data(cells)
ppm(cells, ~ 1, mySH, correction="isotropic")