Generate a random point pattern, a simulated realisation of the Matern Model II inhibition process.
rMaternII(kappa, r, win = owin(c(0,1),c(0,1)), stationary=TRUE, ...,
nsim=1, drop=TRUE)
Intensity of the Poisson process of proposal points. A single positive number.
Inhibition distance.
Window in which to simulate the pattern.
An object of class "owin"
or something acceptable to as.owin
.
Alternatively a higher-dimensional box of class
"box3"
or "boxx"
.
Logical. Whether to start with a stationary process of proposal points
(stationary=TRUE
) or to generate the
proposal points only inside the window (stationary=FALSE
).
Ignored.
Number of simulated realisations to be generated.
Logical. If nsim=1
and drop=TRUE
(the default), the
result will be a point pattern, rather than a list
containing a point pattern.
A point pattern
if nsim=1
, or a list of point patterns if nsim > 1
.
Each point pattern is normally an object of class "ppp"
,
but may be of class "pp3"
or "ppx"
depending on the window.
This algorithm generates one or more realisations
of Matern's Model II
inhibition process inside the window win
.
The process is constructed by first
generating a uniform Poisson point process of ``proposal'' points
with intensity kappa
. If stationary = TRUE
(the
default), the proposal points are generated in a window larger than
win
that effectively means the proposals are stationary.
If stationary=FALSE
then the proposal points are
only generated inside the window win
.
Then each proposal point is marked by an ``arrival time'', a number uniformly distributed in \([0,1]\) independently of other variables.
A proposal point is deleted if it lies within r
units' distance
of another proposal point that has an earlier arrival time.
Otherwise it is retained.
The retained points constitute Matern's Model II.
The difference between Matern's Model I and II is the italicised statement above. Model II has a higher intensity for the same parameter values.
# NOT RUN {
X <- rMaternII(20, 0.05)
Y <- rMaternII(20, 0.05, stationary=FALSE)
# }
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