vrt {terra}R Documentation

Virtual Raster Dataset

Description

Create a Virtual Raster Dataset (VRT) from a collection of file-based raster datasets (tiles).

Usage

## S4 method for signature 'character'
vrt(x, filename="", options=NULL, overwrite=FALSE)

Arguments

x

character. Filenames of raster "tiles". See tiles

filename

character. Output VRT filename

options

character. All arguments as separate vector elements. Options as for gdalbuildvrt

overwrite

logical. Should filename be overwritten if it exists?

Value

SpatRaster

Note

A VRT can reference very many datasets. These are not all opened at the same time. The default is to open not more than 100 files. To increase performance, this maximum limit can be increased by setting the GDAL_MAX_DATASET_POOL_SIZE configuration option to a bigger value with setGDALconfig. Note that a typical user process on Linux is limited to 1024 simultaneously opened files.

See Also

makeTiles to create tiles; makeVRT to create a .vrt file for a binary raster file that does not have a header file.

Examples

r <- rast(ncols=100, nrows=100)
values(r) <- 1:ncell(r)
x <- rast(ncols=2, nrows=2)
filename <- paste0(tempfile(), "_.tif")
ff <- makeTiles(r, x, filename)
ff

#vrtfile <- paste0(tempfile(), ".vrt")
#v <- vrt(ff, vrtfile)


## output in lower resolution
#vrtfile <- paste0(tempfile(), ".vrt")
#v <- vrt(ff, vrtfile, options = c("-tr", 5, 5))
#head(readLines(vrtfile))
#v

[Package terra version 1.6-33 Index]