R: Extend

expand {terra} | R Documentation

## Extend

### Description

Enlarge the spatial extent of a SpatRaster. See `crop` if you (also) want to remove rows or columns.

You can also enlarge a SpatExtent with this method, or with algebraic notation (see examples)

### Usage

    ## S4 method for signature 'SpatRaster'
    extend(x, y, filename="", overwrite=FALSE, ...)

    ## S4 method for signature 'SpatExtent'
    extend(x, y)

### Arguments

`x` | SpatRaster or SpatExtent
`y` | If `x` is a SpatRaster, `y` should be a SpatExtent, or an object from which it can be extracted (such as SpatRaster and SpatVector objects). Alternatively, you can provide two positive integers indicating the number of rows and columns that need to be added at each side (or a single positive integer when the number of rows and columns is equal) If `x` is a SpatExtent, `y` should be a numeric vector of 1, 2, or 4 elements
`filename` | character. Output filename
`overwrite` | logical. If `TRUE`, `filename` is overwritten
`...` | additional arguments for writing files as in `writeRaster`

### Value

SpatRaster or SpatExtent

### See Also

`crop`, `merge`, `ext`

### Examples

    r <- rast(xmin=-150, xmax=-120, ymin=30, ymax=60, ncol=36, nrow=18)
    values(r) <- 1:ncell(r)
    e <- ext(-180, -100, 40, 70)
    re <- extend(r, e)

    # expand with a number of rows and columns (at each side)
    re2 <- extend(r, c(2,10))

    # SpatExtent
    e <- ext(r)
    e
    extend(e, 10)
    extend(e, c(10, -10, 0, 20))

[Package terra version 1.2-5 Index]