Draw an Interactive Japan Map with leaflet — jp_map

jp_map_leaflet() creates a simple interactive web map from jpmap boundaries. It uses literal longitude/latitude geography because Leaflet web tiles expect WGS84 coordinates. Use plot_jpmap() when you want the static Okinawa and Ogasawara inset layout.

Usage

jp_map_leaflet(
  regions = c("prefectures", "prefecture", "municipalities", "municipality"),
  include = c(),
  exclude = c(),
  data = data.frame(),
  values = NULL,
  by = NULL,
  data_year = NULL,
  territorial_disputes = TRUE,
  data_dir = NULL,
  palette = "Blues",
  fill = "grey92",
  color = "grey35",
  weight = 1,
  opacity = 1,
  fill_opacity = 0.75,
  na_color = "#D9D9D9",
  label = NULL,
  popup = NULL,
  tiles = TRUE,
  legend = TRUE,
  fit_bounds = TRUE,
  simplify_tolerance = NULL,
  disputed_fill = NULL,
  disputed_color = NULL,
  disputed_dots = FALSE,
  disputed_dot_radius = 5,
  ...
)

Arguments

regions: Boundary level: prefectures or municipalities.
include: Regions to include by code, English name, or Japanese name.
exclude: Regions to exclude by code, English name, or Japanese name.
data: Optional data frame to join to the map before drawing.
values: Optional column to use for polygon fill colors.
by: Optional join column passed to jp_map_join().
data_year: Boundary data year. The newest appropriate available file is used by default.
territorial_disputes: Whether to include disputed-territory island/reef shapes. Use FALSE to exclude them, or a selected character vector.
data_dir: Optional directory containing jpmap_boundaries_YYYY.gpkg.
palette: Palette name or color vector passed to Leaflet palette functions when values is supplied.
fill: Polygon fill color used when values is NULL.
color: Polygon outline color.
weight: Polygon outline weight.
opacity: Polygon outline opacity.
fill_opacity: Polygon fill opacity.
na_color: Fill color for missing values.
label: NULL for default region labels, FALSE for no labels, a column name, or a character vector with one value per map row.
popup: NULL for default popups, FALSE for no popups, a column name, or a character vector with one value per map row.
tiles: Whether to add default OpenStreetMap tiles.
legend: Whether to add a legend when values is supplied.
fit_bounds: Whether to zoom the widget to the map bounds.
simplify_tolerance: Optional tolerance passed to sf::st_simplify() before drawing polygons. This is useful for smaller website widgets.
disputed_fill: Optional fill color for disputed-territory shapes. When NULL, the ordinary map fill is used.
disputed_color: Optional outline color for disputed-territory shapes. When NULL, the ordinary map outline is used.
disputed_dots: Whether to draw circle markers on disputed-territory shapes.
disputed_dot_radius: Radius for disputed-territory circle markers.
...: Additional arguments passed to leaflet::leaflet().

Value

A leaflet htmlwidget.

Examples

if (requireNamespace("leaflet", quietly = TRUE) &&
    requireNamespace("dplyr", quietly = TRUE) &&
    nrow(available_jpmap_data()) > 0) {
  data("jp_prefecture_gdp")

  gdp <- jp_prefecture_gdp |>
    dplyr::select(pref_code, prefecture, gdp_per_capita_jpy)

  jp_map_leaflet(
    "prefecture",
    data = gdp,
    values = "gdp_per_capita_jpy",
    popup = "prefecture"
  )
}