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\name{getValuesFocal}
\alias{getValuesFocal}
\alias{getValuesFocal,Raster-method}
\alias{getValuesFocal,Raster,missing,missing,numeric-method}
\alias{getValuesFocal,Raster,numeric,numeric,numeric-method}
\title{Get focal raster cell values}
\description{
This function returns a matrix (or matrices) for all focal values of a number of rows of a Raster* object}
\usage{
\S4method{getValuesFocal}{Raster}(x, row, nrows, ngb, names=FALSE, padValue=NA, array=FALSE, ...)
}
\arguments{
\item{x}{Raster* object}
\item{row}{Numeric. Row number, should be between 1 and nrow(x). Can be omitted to get all rows}
\item{nrows}{Numeric. Number of rows, should be a positive integer smaller than \code{row+nrow(x)}. Should be omitted if \code{row} is omitted}
\item{ngb}{Neighbourhood size. Either a single integer or a vector of two integers \code{c(nrow, ncol)}}
\item{names}{logical. If \code{TRUE}, the matrix returned has row and column names}
\item{padValue}{numeric. The value of the cells of the "padded" rows and columns. That is 'virtual' values for cells within a neighbourhood, but outside the raster}
\item{array}{logical. If \code{TRUE} and \code{x} has multiple layers, an array is returned in stead of a list of matrices}
\item{...}{additional arguments (none implemented)}
}
\value{
If \code{x} has a single layer, a matrix with one row for each focal cell, and one column for each neighbourhood cell around it.
If \code{x} has multiple layers, an array (if \code{array=TRUE}) or a list of such matrices (one list element (matrix) for each layer)
}
\seealso{ \code{\link{getValues}, \link{focal}} }
\examples{
r <- raster(nr=5, nc=5, crs='+proj=utm +zone=12')
values(r) <- 1:25
as.matrix(r)
getValuesFocal(r, row=1, nrows=2, ngb=3, names=TRUE)
getValuesFocal(stack(r,r), row=1, nrows=1, ngb=3, names=TRUE, array=TRUE)
}
\keyword{spatial}
\keyword{methods}
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