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Erase or trim geometry of a sf or sfc object

Source: R/st_erase.R
st_erase.Rd

st_erase() extends sf::st_difference() by unioning the second parameter by default, checking validity of inputs, and optionally (when flip = TRUE) using sf::st_intersection() instead of sf::st_difference. st_trim() is equivalent to st_erase() with flip set to TRUE.

Usage

st_erase(x, y, flip = FALSE, union = TRUE, combine = FALSE, ...)

st_trim(x, y, union = TRUE, combine = FALSE, ...)

Arguments

x

A sf, sfc, or bbox object to erase or trim.

y

A sf, sfc, or bbox object to use to erase or trim.

flip

If TRUE, use sf::st_intersection() to "erase" geometry of x that intersects y; if FALSE use sf::st_difference() to trim x to y geometry, Default: FALSE.

union

If TRUE, union y with sf::st_union() before applying difference/intersection; defaults to TRUE.

combine

If TRUE and union = TRUE, combine y with sf::st_combine() before unioning. Defaults to FALSE.

...

arguments passed on to s2_options

Examples

nc <- read_sf_ext(system.file("shape/nc.shp", package = "sf"))

nc <- st_transform_ext(nc, 3657)

plot(
  st_erase(
    sf::st_buffer(nc[1, ], 1000),
    nc[1, ]
  ),
  max.plot = 1
)


plot(
  st_trim(
    nc,
    sf::st_buffer(nc[1, ], 2000)
  ),
  max.plot = 1
)