get substring from linestring

Usage

st_linesubstring(x, from, to, tolerance, ...)

Arguments

x: object of class sfc, sf or sfg
from: relative distance from origin (in [0,1])
to: relative distance from origin (in [0,1])
tolerance: tolerance parameter, when to snap to line node node
...: ignored

Value

object of class sfc

Examples

library(sf)
lines = st_sfc(st_linestring(rbind(c(0,0), c(1,2), c(2,0))), crs = 4326)
spl = st_linesubstring(lines, 0.2, 0.8) # should warn
#> Warning: st_linesubstring does not follow a geodesic; you may want to use st_geod_segmentize first
plot(st_geometry(lines), col = 'red', lwd = 3)
plot(spl, col = 'black', lwd = 3, add = TRUE)

st_linesubstring(lines, 0.49999, 0.8) # three points
#> Warning: st_linesubstring does not follow a geodesic; you may want to use st_geod_segmentize first
#> Geometry set for 1 feature 
#> Geometry type: LINESTRING
#> Dimension:     XY
#> Bounding box:  xmin: 0.99998 ymin: 0.8 xmax: 1.6 ymax: 2
#> Geodetic CRS:  WGS 84
#> LINESTRING (0.99998 1.99996, 1 2, 1.6 0.8)
st_linesubstring(lines, 0.49999, 0.8, 0.001) # two points: snap start to second node
#> Warning: st_linesubstring does not follow a geodesic; you may want to use st_geod_segmentize first
#> Geometry set for 1 feature 
#> Geometry type: LINESTRING
#> Dimension:     XY
#> Bounding box:  xmin: 1 ymin: 0.8 xmax: 1.6 ymax: 2
#> Geodetic CRS:  WGS 84
#> LINESTRING (1 2, 1.6 0.8)