For a model that was fitted by optimisation, compute the values of the objective function in a neighbourhood of the optimal value.
objsurf(x, …)# S3 method for dppm
objsurf(x, ..., ngrid = 32, ratio = 1.5, verbose = TRUE)
# S3 method for kppm
objsurf(x, ..., ngrid = 32, ratio = 1.5, verbose = TRUE)
# S3 method for minconfit
objsurf(x, ..., ngrid = 32, ratio = 1.5, verbose = TRUE)
Some kind of model that was fitted
by finding the optimal value of an objective function.
An object of class "dppm"
, "kppm"
or "minconfit"
.
Extra arguments are usually ignored.
Number of grid points to evaluate along each axis.
Either a single integer, or a pair of integers.
For example ngrid=32
would mean a 32 * 32
grid.
Number greater than 1 determining the range of parameter values
to be considered. If the optimal parameter value is opt
then the objective function will be evaluated for
values between opt/ratio
and opt * ratio
.
Logical value indicating whether to print progress reports.
An object of class "objsurf"
which can be
printed and plotted.
Essentially a list containing entries x
, y
, z
giving the parameter values and objective function values.
The object x
should be some kind of model that was fitted
by maximising or minimising the value of an objective function.
The objective function will be evaluated on a grid of
values of the model parameters.
Currently the following types of objects are accepted:
an object of class "dppm"
representing a
determinantal point process.
See dppm
.
an object of class "kppm"
representing a
cluster point process or Cox point process.
See kppm
.
an object of class "minconfit"
representing a
minimum-contrast fit between a summary function and its
theoretical counterpart.
See mincontrast
.
The result is an object of class "objsurf"
which can be
printed and plotted: see methods.objsurf
.
# NOT RUN {
fit <- kppm(redwood ~ 1, "Thomas")
os <- objsurf(fit)
if(interactive()) {
plot(os)
contour(os, add=TRUE)
persp(os)
}
# }
Run the code above in your browser using DataLab