Project point on linestring, interpolate along a linestring

Usage

st_line_project(line, point, normalized = FALSE)

st_line_interpolate(line, dist, normalized = FALSE)

Arguments

line: object of class sfc with LINESTRING geometry
point: object of class sfc with POINT geometry
normalized: logical; if TRUE, use or return distance normalised to 0-1
dist: numeric, vector with distance value(s)

Value

st_line_project returns the distance(s) of point(s) along line(s), when projected on the line(s)

st_line_interpolate returns the point(s) at dist(s), when measured along (interpolated on) the line(s)

Details

arguments line, point and dist are recycled to common length when needed

Examples

st_line_project(st_as_sfc("LINESTRING (0 0, 10 10)"), st_as_sfc(c("POINT (0 0)", "POINT (5 5)")))
#> [1] 0.000000 7.071068
st_line_project(st_as_sfc("LINESTRING (0 0, 10 10)"), st_as_sfc("POINT (5 5)"), TRUE)
#> [1] 0.5
st_line_interpolate(st_as_sfc("LINESTRING (0 0, 1 1)"), 1)
#> Geometry set for 1 feature 
#> Geometry type: POINT
#> Dimension:     XY
#> Bounding box:  xmin: 0.7071068 ymin: 0.7071068 xmax: 0.7071068 ymax: 0.7071068
#> CRS:           NA
#> POINT (0.7071068 0.7071068)
st_line_interpolate(st_as_sfc("LINESTRING (0 0, 1 1)"), 1, TRUE)
#> Geometry set for 1 feature 
#> Geometry type: POINT
#> Dimension:     XY
#> Bounding box:  xmin: 1 ymin: 1 xmax: 1 ymax: 1
#> CRS:           NA
#> POINT (1 1)