discrete-scale: Add discrete scale to a map

In dreamRs/r2d3maps: Create Maps with D3

Description

Display a discrete value on a map. add_discrete_scale is for using a color palette, add_discrete_scale2 is to attach custom colors to data levels.

Usage

add_discrete_scale(map, var, palette = "viridis", direction = 1,
  na_color = "#D8D8D8", labels_order = NULL)

add_discrete_scale2(map, var, values, na_color = "#D8D8D8")

Arguments

map	A r2d3map htmlwidget object.
var	Variable to map
palette	Color palette, you can use Viridis or Brewer color palette.
direction	Sets the order of colors in the scale. If 1, the default, colors are ordered from darkest to lightest. If -1, the order of colors is reversed.
na_color	Color to use for missing values.
labels_order	Vector of unique values for changing order of labels in legend.
values	Named list mapping data values to colors. It's recommended to use Hex color code without alpha, e.g. # followed by 6 chars [0-9a-f].

Examples

library( r2d3maps )
library( rnaturalearth )

# data
japan <- ne_states(country = "japan", returnclass = "sf")

# Japan's regions
d3_map(shape = japan) %>%
  add_discrete_scale(var = "region")

# different color palette
d3_map(shape = japan) %>%
  add_discrete_scale(var = "region", palette = "Set2")

# custom colors
d3_map(shape = japan) %>%
  add_discrete_scale2(
    var = "region",
    values = list(
      "Chugoku" = "#000080",
      "Kyushu" = "#6B8E23",
      "Shikoku" = "#DDA0DD",
      "Chubu" = "#4169E1",
      "Kinki" = "#2E8B57",
      "Hokkaido" = "#4682B4",
      "Kanto" = "#FFA07A",
      "Tohoku" = "#F08080",
      "Okinawa" = "red"
    ),
    na_color = "#000"
  )

# with legend
d3_map(shape = japan) %>%
  add_discrete_scale(var = "region", palette = "Set1") %>%
  add_legend(title = "County")

dreamRs/r2d3maps documentation built on May 25, 2019, 8:17 a.m.