R: Get focal raster cell values

getValuesFocal {raster} | R Documentation

## 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

    ## S4 method for signature 'Raster'
    getValuesFocal(x, row, nrows, ngb, names=FALSE, padValue=NA, array=FALSE, ...)

### Arguments

`x` | Raster* object
`row` | Numeric. Row number, should be between 1 and nrow(x). Can be omitted to get all rows
`nrows` | Numeric. Number of rows, should be a positive integer smaller than `row+nrow(x)`. Should be omitted if `row` is omitted
`ngb` | Neighbourhood size. Either a single integer or a vector of two integers `c(nrow, ncol)`
`names` | logical. If `TRUE`, the matrix returned has row and column names
`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
`array` | logical. If `TRUE` and `x` has multiple layers, an array is returned in stead of a list of matrices
`...` | additional arguments (none implemented)

### Value

If `x` has a single layer, a matrix with one row for each focal cell, and one column for each neighbourhood cell around it.

If `x` has multiple layers, an array (if `array=TRUE`) or a list of such matrices (one list element (matrix) for each layer)

### See Also

`getValues, 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)

[Package raster version 3.0-7 Index]