Manage jpmap Boundary Data

Helpers for locating and building the GeoPackage boundary data used by jpmap. Boundary GeoPackage files can come from the separate jpmapdata package or from files built locally with jpmap_build_data().

Usage

jpmap_data_dir(create = TRUE)

available_jpmap_data(data_dir = NULL)

jpmap_build_data(
  year = 2024,
  prefecture = NULL,
  destdir = jpmap_data_dir(),
  url = NULL,
  overwrite = FALSE,
  quiet = FALSE,
  simplify_tolerance = NULL
)

Arguments

create

Whether to create the default data directory.

data_dir

Optional directory to scan for boundary data.

year

Boundary data year.

prefecture

Optional prefecture code, English name, or Japanese name. When supplied, only that prefecture's official MLIT N03 file is downloaded and built.

destdir

Directory where the generated GeoPackage should be written.

url

Optional source URL. By default, an MLIT N03 URL is constructed.

overwrite

Whether to overwrite an existing GeoPackage.

quiet

Whether to suppress messages from download and spatial reads/writes.

simplify_tolerance

Optional tolerance passed to sf::st_simplify().

Value

jpmap_data_dir() returns a path, available_jpmap_data() returns a data frame with year, pref_code, prefecture, source, and path, and jpmap_build_data() invisibly returns the generated file.

Source

MLIT National Land Numerical Information N03 administrative area data: https://nlftp.mlit.go.jp/ksj/gml/datalist/KsjTmplt-N03-2024.html.

Examples

if (FALSE) { # \dontrun{
jpmap_build_data(year = 2024)
jpmap_build_data(year = 2024, prefecture = "Ehime")
available_jpmap_data()
} # }