Return properties of layers in a datasource as data.frame

Return properties of layers in a datasource as data.frame

st_layers_as_df(x, ..., drop_driver = TRUE, warn = TRUE)

Arguments

x

any input that works for st_layers's argument dsn or an object of class sf_layers

...

arguments of the function st_layers except dsn if x is equivalent to dsn else ignored

drop_driver

logical; TRUE (default) drops information about the driver, FALSE adds the driver as column to the returned data.frame

warn

logical; TRUE (default) warns if no layer is available, FALSE does not warn in such a case

Value

if no layer is available NULL, else a data.frame resembling the printed return of st_layers with columns

layer_name

name of the layer

geometry_type or geometry_types

for each layer a string listing its geometry type(s)

features

number of features (if reported; see argument do_count of st_layers)

fields

number of fields

crs

short name of each layer's crs

driver (optional)

name of driver, if argument drop_driver has been set to FALSE

Examples

library(sf)
dsn <- system.file("shape", package = "sf")
st_layers_as_df(x = dsn, drop_driver = FALSE)
#>            layer_name        geometry_type features fields             crs_name
#> 1  storms_xyz_feature       3D Line String       71      1                 <NA>
#> 2 storms_xyzm_feature Measured Line String       71      1                 <NA>
#> 3          storms_xyz       3D Line String       71      0                 <NA>
#> 4                  nc              Polygon      100     14                NAD27
#> 5         storms_xyzm Measured Line String       71      0                 <NA>
#> 6             olinda1              Polygon      470      6 GRS 1980(IUGG, 1980)
#>           driver
#> 1 ESRI Shapefile
#> 2 ESRI Shapefile
#> 3 ESRI Shapefile
#> 4 ESRI Shapefile
#> 5 ESRI Shapefile
#> 6 ESRI Shapefile

# properties of layers of multiple datasources in one data.frame
some_dsn <- list.files(system.file("gpkg", package = "sf"), full.names = TRUE)
multiple_dsn <- c(dsn, some_dsn)
df <-
  as.list(multiple_dsn) %>%
  setNames(multiple_dsn) %>%
  lapply(st_layers_as_df, drop_driver = FALSE) %>%
  data.table::rbindlist(use.names = FALSE, idcol = "dsn")