https://github.com/cran/spatstat
Tip revision: 2bcb37fef517ce03cdd4a375eb4be390aaaacb20 authored by Adrian Baddeley on 23 June 2019, 13:40:07 UTC
version 1.60-1
version 1.60-1
Tip revision: 2bcb37f
shift.im.Rd
\name{shift.im}
\alias{shift.im}
\title{Apply Vector Translation To Pixel Image}
\description{
Applies a vector shift to a pixel image
}
\usage{
\method{shift}{im}(X, vec=c(0,0), \dots, origin=NULL)
}
\arguments{
\item{X}{Pixel image (object of class \code{"im"}).}
\item{vec}{Vector of length 2 representing a translation.}
\item{\dots}{Ignored}
\item{origin}{
Location that will be shifted to the origin.
Either a numeric vector of length 2 giving the location,
or a point pattern containing only one point,
or a list with two entries named \code{x} and \code{y},
or one of the character strings
\code{"centroid"}, \code{"midpoint"},
\code{"left"}, \code{"right"}, \code{"top"}, \code{"bottom"},
\code{"topleft"}, \code{"bottomleft"}, \code{"topright"} or
\code{"bottomright"} (partially matched).
}
}
\value{
Another pixel image (of class \code{"im"}) representing the
result of applying the vector shift.
}
\details{
The spatial location of each pixel in the image
is translated by the vector \code{vec}.
This is a method for the generic function \code{\link{shift}}.
If \code{origin} is given,
the argument \code{vec} will be ignored; instead the shift will be performed
so that the specified geometric location is shifted to the
coordinate origin \eqn{(0,0)}.
The argument \code{origin} should be either a numeric vector of length
2 giving the spatial coordinates of a location, or one of the character
strings \code{"centroid"}, \code{"midpoint"},
\code{"left"}, \code{"right"}, \code{"top"}, \code{"bottom"},
\code{"topleft"}, \code{"bottomleft"}, \code{"topright"} or
\code{"bottomright"} (partially matched).
If \code{origin="centroid"} then the centroid of the window will be
shifted to the origin. If \code{origin="midpoint"} then the centre of
the bounding rectangle of the window will be shifted to the origin.
If \code{origin="bottomleft"} then the bottom left corner of the
bounding rectangle of the window will be shifted to the origin,
and so on.
}
\seealso{
\code{\link{shift}}
}
\examples{
# make up an image
X <- setcov(unit.square())
plot(X)
Y <- shift(X, c(10,10))
plot(Y)
# no discernible difference except coordinates are different
shift(X, origin="c")
}
\author{\adrian
and \rolf
}
\keyword{spatial}
\keyword{manip}