envelope.envelope.Rd
\name{envelope.envelope}
\alias{envelope.envelope}
\title{
Recompute Envelopes
}
\description{
Given a simulation envelope (object of class \code{"envelope"}),
compute another envelope from the same simulation data
using different parameters.
}
\usage{
\method{envelope}{envelope}(Y, fun = NULL, ...,
transform=NULL, global=FALSE, VARIANCE=FALSE)
}
\arguments{
\item{Y}{
A simulation envelope (object of class \code{"envelope"}).
}
\item{fun}{
Optional. Summary function to be applied to the simulated point patterns.
}
\item{\dots,transform,global,VARIANCE}{
Parameters controlling the type of envelope that is re-computed.
See \code{\link{envelope}}.
}
}
\details{
This function can be used to re-compute a simulation envelope
from previously simulated data, using different parameter settings
for the envelope: for example, a different
significance level, or a global envelope instead of a pointwise
envelope.
The function \code{\link{envelope}} is generic. This is the method for
the class \code{"envelope"}.
The argument \code{Y} should be a simulation envelope (object of
class \code{"envelope"}) produced by any of the methods for
\code{\link{envelope}}. Additionally, \code{Y} must contain either
\itemize{
\item the simulated point patterns that were used to create
the original envelope (so \code{Y} should have been created by calling
\code{\link{envelope}} with \code{savepatterns=TRUE});
\item the summary functions of the simulated point patterns
that were used to create
the original envelope (so \code{Y} should have been created by calling
\code{\link{envelope}} with \code{savefuns=TRUE}).
}
If the argument \code{fun} is given, it should be a summary function
that can be applied to the simulated point patterns that were
used to create \code{Y}. The envelope of
the summary function \code{fun} for these point patterns
will be computed using the parameters specified in \code{\dots}.
If \code{fun} is not given, then:
\itemize{
\item
If \code{Y} contains the summary functions that were used to
compute the original envelope, then the new envelope will be
computed from these original summary functions.
\item
Otherwise, if \code{Y} contains the simulated point patterns.
then the \eqn{K} function \code{\link{Kest}} will be applied to
each of these simulated point patterns, and the new envelope will
be based on the \eqn{K} functions.
}
The new envelope
will be computed using the parameters specified in \code{\dots}.
See \code{\link{envelope}} for a full list of envelope parameters.
Frequently-used parameters include \code{nrank} and \code{nsim} (to change the
number of simulations used and the significance level of the
envelope), \code{global} (to change from pointwise to global
envelopes) and \code{VARIANCE} (to compute the envelopes from the sample
moments instead of the ranks).
}
\value{
An envelope (object of class \code{"envelope"}.
}
\seealso{
\code{\link{envelope}}
}
\examples{
E <- envelope(cells, Kest, nsim=19, savefuns=TRUE, savepatterns=TRUE)
E2 <- envelope(E, nrank=2)
Eg <- envelope(E, global=TRUE)
EG <- envelope(E, Gest)
EL <- envelope(E, transform=expression(sqrt(./pi)))
}
\author{\adrian
and \rolf
}
\keyword{spatial}
\keyword{htest}
\keyword{hplot}
\keyword{iteration}