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Union simple feature objects and combine name column values

Source: R/st_union_ext.R
st_union_ext.Rd

Wrapper for sf::st_union() supporting the additional feature of a combined name column collapsed into a single vector with cli::pluralize(). st_union_by() wraps dplyr::group_by() and dplyr::summarise() to allow quick unioning geometry by the passed parameters.

Usage

st_union_ext(
  x,
  y = NULL,
  name_col = "name",
  .sf_col = NULL,
  label = NULL,
  ext = TRUE,
  ...
)

st_union_by(x, ..., .sf_col = NULL)

Arguments

x

A sf, sfc, or bbox object or sf only for st_union_by() Required.

y

A sf or sfc object, defaults to NULL.

name_col

Column name to collapse into new name_col value, Default: 'name'

.sf_col

Geometry column name to use if x is an sf object, Default: NULL.

label

Length 1 character vector used if name_col is NULL.

ext

If FALSE, st_union_ext() functions the same as sf::st_union(), Default: TRUE

...

Additional parameters passed to sf::st_union() or dplyr::group_by().

Value

A sfc object if y is NULL and ext is FALSE. A tibble sf if x is a sf object and y is NULL. If y is provided, st_union_ext() is identical to sf::st_union()

Examples

nc <- read_sf_path(system.file("shape/nc.shp", package = "sf"))
nc_union <- st_union_ext(nc[10:15,], name_col = "NAME")
nc_union
#> Simple feature collection with 1 feature and 1 field
#> Geometry type: POLYGON
#> Dimension:     XY
#> Bounding box:  xmin: -80.45301 ymin: 36.01413 xmax: -78.28293 ymax: 36.55104
#> Geodetic CRS:  NAD27
#> # A tibble: 1 × 2
#>   NAME                                                                  geometry
#>   <chr>                                                            <POLYGON [°]>
#> 1 Stokes, Caswell, Rockingham, Granville, Person, and… ((-79.2585 36.23569, -79…
plot(nc_union)