R: Get a block of raster cell values

getValuesBlock {raster} | R Documentation

## Get a block of raster cell values

### Description

getValuesBlock returns values for a block (rectangular area) of values of a Raster* object.

### Usage

    ## S4 method for signature 'RasterLayer'
    getValuesBlock(x, row=1, nrows=1, col=1, ncols=(ncol(x)-col+1), format='', ...)

    ## S4 method for signature 'RasterBrick'
    getValuesBlock(x, row=1, nrows=1, col=1, ncols=(ncol(x)-col+1), lyrs, ...)

    ## S4 method for signature 'RasterStack'
    getValuesBlock(x, row=1, nrows=1, col=1, ncols=(ncol(x)-col+1), lyrs, ...)

### Arguments

`x` | Raster* object
`row` | positive integer. Row number to start from, should be between 1 and nrow(x)
`nrows` | postive integer. How many rows? Default is 1
`col` | postive integer. Column number to start from, should be between 1 and ncol(x)
`ncols` | postive integer. How many columns? Default is the number of colums left after the start column
`format` | character. When `x` is a `RasterLayer`, if `format='matrix'` or `format='m'`, a matrix is returned instead of a vector. If `format='matrix'`, it is a nrow x ncol matrix. If `format='m'` it is a 1 column matrix (the benefit is that the type of output is now the same for all Raster objects)
`lyrs` | integer (vector). Which layers? Default is all layers (`1:nlayers(x)`)
`...` | additional arguments (none implemented)

### Value

matrix or vector (if `(x=RasterLayer)`, unless `format='matrix'`)

### See Also

`getValues`

### Examples

    r <- raster(system.file("external/test.grd", package="raster"))
    b <- getValuesBlock(r, row=100, nrows=3, col=10, ncols=5)
    b
    b <- matrix(b, nrow=3, ncol=5, byrow=TRUE)
    b

    logo <- brick(system.file("external/rlogo.grd", package="raster"))
    getValuesBlock(logo, row=35, nrows=3, col=50, ncols=3, lyrs=2:3)

[Package raster version 2.6-7 Index]