as.lines: Conversion to a SpatVector of lines

In terra: Spatial Data Analysis

Conversion to a SpatVector of lines

Description

Conversion of a SpatRaster, SpatVector or SpatExtent to a SpatVector of lines.

Usage

## S4 method for signature 'SpatRaster'
as.lines(x, na.rm=FALSE)

## S4 method for signature 'SpatVector'
as.lines(x)

## S4 method for signature 'SpatExtent'
as.lines(x, crs="")

## S4 method for signature 'matrix'
as.lines(x, crs="", segments=FALSE)

Arguments

x	SpatRaster, SpatVector, SpatExtent or matrix. If x is a matrix it should have two columns for a single line, or four columns, where each row has the start and end coordinates (x, y) for lines
na.rm	logical. Only show lines for cells that are not NA?
crs	character. The coordinate reference system (see crs)
segments	logical. Should (poly-)lines or polygons be disaggregated into their line-segments? See disagg

Value

SpatVector

See Also

as.points, as.polygons

Examples

r <- rast(ncols=2, nrows=2)
values(r) <- 1:ncell(r)

as.lines(r)

as.lines(ext(r), crs=crs(r))

p <- as.polygons(r)
as.lines(p)


## with a matrix
s <- cbind(1:5, 1:5)
e <- cbind(1:5, 0)

as.lines(s)
as.lines(cbind(s, e), "+proj=longlat")

terra documentation built on Aug. 22, 2026, 5:07 p.m.