marks.psp.Rd
\name{marks.psp}
\alias{marks.psp}
\alias{marks<-.psp}
\title{Marks of a Line Segment Pattern}
\description{
Extract or change the marks attached to
a line segment pattern.
}
\usage{
\method{marks}{psp}(x, \dots, dfok=TRUE)
\method{marks}{psp}(x, \dots) <- value
}
\arguments{
\item{x}{
Line segment pattern dataset (object of class \code{"psp"}).
}
\item{\dots}{
Ignored.
}
\item{dfok}{
Logical. If \code{FALSE}, data frames of marks are not permitted
and will generate an error.
}
\item{value}{
Vector or data frame of mark values,
or \code{NULL}.
}
}
\value{
For \code{marks(x)}, the result is a vector, factor or data frame,
containing the mark values attached to the line segments of \code{x}.
If there are no marks, the result is \code{NULL}.
For \code{marks(x) <- value}, the result is the updated line segment pattern
\code{x} (with the side-effect that the dataset \code{x} is updated in
the current environment).
}
\details{
These functions extract or change the marks
attached to each of the line segments in the pattern \code{x}.
They are methods for the generic functions
\code{\link{marks}} and \code{\link{marks<-}}
for the class \code{"psp"} of line segment patterns.
The expression \code{marks(x)} extracts the marks of \code{x}.
The assignment \code{marks(x) <- value} assigns new marks to the
dataset \code{x}, and updates the dataset \code{x} in the current
environment.
The marks can be a vector, a factor, or a data frame.
For the assignment \code{marks(x) <- value}, the \code{value}
should be a vector or factor of length equal to the number of
segments in \code{x}, or a data frame with as many rows
as there are segments in \code{x}. If \code{value} is a single value,
or a data frame with one row, then it will be replicated
so that the same marks will be attached to each segment.
To remove marks, use \code{marks(x) <- NULL} or \code{unmark(x)}.
}
\seealso{
\code{\link{psp.object}},
\code{\link{marks}},
\code{\link{marks<-}}
}
\examples{
m <- data.frame(A=1:10, B=letters[1:10])
X <- psp(runif(10), runif(10), runif(10), runif(10), window=owin(), marks=m)
marks(X)
marks(X)[,2]
marks(X) <- 42
marks(X) <- NULL
}
\author{
\spatstatAuthors.
}
\keyword{spatial}
\keyword{manip}