is.hybrid.Rd
\name{is.hybrid}
\alias{is.hybrid}
\alias{is.hybrid.ppm}
\alias{is.hybrid.interact}
\title{
Test Whether Object is a Hybrid
}
\description{
Tests where a point process model or point process interaction
is a hybrid of several interactions.
}
\usage{
is.hybrid(x)
\method{is.hybrid}{ppm}(x)
\method{is.hybrid}{interact}(x)
}
\arguments{
\item{x}{
A point process model (object of class \code{"ppm"})
or a point process interaction structure
(object of class \code{"interact"}).
}
}
\details{
A \emph{hybrid} (Baddeley, Turner, Mateu and Bevan, 2012)
is a point process model created by combining two or more
point process models, or an interpoint interaction created by combining
two or more interpoint interactions.
The function \code{is.hybrid} is generic, with methods for
point process models (objects of class \code{"ppm"})
and point process interactions
(objects of class \code{"interact"}).
These functions return \code{TRUE} if the object \code{x} is a hybrid,
and \code{FALSE} if it is not a hybrid.
Hybrids of two or more interpoint interactions
are created by the function \code{\link{Hybrid}}.
Such a hybrid interaction can then be fitted to point pattern data
using \code{\link{ppm}}.
}
\value{
\code{TRUE} if the object is a hybrid, and \code{FALSE} otherwise.
}
\references{
Baddeley, A., Turner, R., Mateu, J. and Bevan, A. (2012)
Hybrids of Gibbs point process models and their implementation.
Submitted for publication.
}
\seealso{
\code{\link{Hybrid}}
}
\examples{
S <- Strauss(0.1)
is.hybrid(S)
H <- Hybrid(Strauss(0.1), Geyer(0.2, 3))
is.hybrid(H)
data(redwood)
fit <- ppm(redwood, ~1, H)
is.hybrid(fit)
}
\author{Adrian Baddeley
\email{Adrian.Baddeley@csiro.au}
\url{http://www.maths.uwa.edu.au/~adrian/}
and Rolf Turner
\email{r.turner@auckland.ac.nz}
}
\keyword{spatial}
\keyword{models}