R: Extent

extent {raster} | R Documentation

## Extent

### Description

This function returns an Extent object of a Raster* or Spatial* object (or an Extent object), or creates an Extent object from a 2x2 matrix (first row: xmin, xmax; second row: ymin, ymax), vector (length=4; order= xmin, xmax, ymin, ymax) or list (with at least two elements, with names 'x' and 'y')

`bbox` returns a `sp` package like 'bbox' object (a matrix)

### Usage

    extent(x, ...)

### Arguments

`x` | Raster* or Extent object, a matrix, or a vector of four numbers
`...` | Additional arguments. When x is a single number representing 'xmin', you can pass three additional numbers (xmax, ymin, ymax) When `x` is a Raster* object, you can pass four additional arguments to crop the extent: `r1, r2, c1, c2`, representing the first and last row and column number

### Value

Extent object

### Author(s)

Robert J. Hijmans; Etienne Racine wrote the extent function for a list

### See Also

`extent`, `drawExtent`

### Examples

    r <- raster()
    extent(r)
    extent(c(0, 20, 0, 20))
    #is equivalent to
    extent(0, 20, 0, 20)
    extent(matrix(c(0, 0, 20, 20), nrow=2))
    x <- list(x=c(0,1,2), y=c(-3,5))
    extent(x)

    #crop the extent by row and column numbers
    extent(r, 1, 20, 10, 30)

[Package raster version 2.5-8 Index]