Persiapan Data

# opsional, jika belum terinstall
# install.packages(c("sf","dplyr"))

library(sf)
library(dplyr)

# membaca shape file
# SHP dari humdata: https://ipb.link/humdata-indonesia-shp

mapIndonesia <- st_read("map/shp/idn_admbnda_adm3_bps_20200401.shp", 
                        quiet = TRUE)
glimpse(mapIndonesia)

## Rows: 7,069
## Columns: 17
## $ Shape_Leng <dbl> 0.2798656, 0.7514001, 0.6900061, 0.6483629, 0.2437073, 1.35~
## $ Shape_Area <dbl> 0.003107633, 0.016925540, 0.024636382, 0.010761277, 0.00116~
## $ ADM3_EN    <chr> "2 X 11 Enam Lingkung", "2 X 11 Kayu Tanam", "Abab", "Abang~
## $ ADM3_PCODE <chr> "ID1306050", "ID1306052", "ID1612030", "ID5107050", "ID7471~
## $ ADM3_REF   <chr> NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA,~
## $ ADM3ALT1EN <chr> NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA,~
## $ ADM3ALT2EN <chr> NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA,~
## $ ADM2_EN    <chr> "Padang Pariaman", "Padang Pariaman", "Penukal Abab Lematan~
## $ ADM2_PCODE <chr> "ID1306", "ID1306", "ID1612", "ID5107", "ID7471", "ID9432",~
## $ ADM1_EN    <chr> "Sumatera Barat", "Sumatera Barat", "Sumatera Selatan", "Ba~
## $ ADM1_PCODE <chr> "ID13", "ID13", "ID16", "ID51", "ID74", "ID94", "ID94", "ID~
## $ ADM0_EN    <chr> "Indonesia", "Indonesia", "Indonesia", "Indonesia", "Indone~
## $ ADM0_PCODE <chr> "ID", "ID", "ID", "ID", "ID", "ID", "ID", "ID", "ID", "ID",~
## $ date       <date> 2019-12-20, 2019-12-20, 2019-12-20, 2019-12-20, 2019-12-20~
## $ validOn    <date> 2020-04-01, 2020-04-01, 2020-04-01, 2020-04-01, 2020-04-01~
## $ validTo    <date> NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA~
## $ geometry   <MULTIPOLYGON [°]> MULTIPOLYGON (((100.2811 -0..., MULTIPOLYGON (~

# membaca data penduduk dari csv

dataBogor <- read.csv("data/Penduduk-Bogor.csv")
dataBogor

# Join ke-dua table

mapBogor<- mapIndonesia %>%
  inner_join(dataBogor, by = c("ADM3_PCODE" = "KodeBPS"))
mapBogor

Peta Leaflet

# opsional, jika belum terinstal
# install.packages("leaflet")

library(leaflet)

# membuat custom palette warna
populationPalette <- colorNumeric(
  palette = "YlGnBu",
  domain = mapBogor$JumlahPenduduk
)

# membuat custom popup
popupLabel <- paste0(
    "<b>Kecamatan ", mapBogor$Kecamatan,"</b><br/>", 
    "Jumlah Penduduk (jiwa): ", mapBogor$JumlahPenduduk, "<br/>", 
    "Luas Wilayah (km2): ", mapBogor$LuasWilayah, "<br/>", 
    "Kepadatan Penduduk (jiwa/km2): ", mapBogor$KepadatanPenduduk) %>%
  lapply(htmltools::HTML)

# membuat peta leaflet
m <- leaflet(mapBogor) %>% 

  # Provider basemap: https://leaflet-extras.github.io/leaflet-providers/preview/
  addProviderTiles(providers$CartoDB.PositronNoLabels, group = "Light Mode") %>%
  addProviderTiles(providers$CartoDB.DarkMatterNoLabels, group = "Dark Mode") %>%
  
  addPolygons(weight = 1,
              opacity = 1, 
              fillOpacity = 0.9,
              label = popupLabel,
              color = ~populationPalette(JumlahPenduduk),
              highlightOptions = highlightOptions(color = "white", 
                                                  weight = 2, 
                                                  bringToFront = TRUE) ) %>%
  addLegend(position = "bottomright", 
            pal = populationPalette, 
            values = ~JumlahPenduduk,
            title = "Jumlah Penduduk",
            opacity = 1) %>%
  
  addLayersControl(position = 'topright',
                   baseGroups = c("Light Mode", "Dark Mode"),
                   options = layersControlOptions(collapsed = FALSE)) %>%
  
  setView(lat = - 6.595, lng = 106.87, zoom = 12)

# tampilkan
m

Penjelasan:

1. leaflet(): inisiasi peta dengan memanggil fungsi leaflet()
2. addProviderTiles(): menambahkan peta dasar (base map) dengan perintah. Bisa juga dengan addTiles() untuk peta dasar default
3. addPolygons(): menabahkan poligon dengan gradasi warna berdasarkan jumlah penduduk. Pengaturan warna gradasi menggunakan colorNumeric(). Ditambahkan pula opsi label untu menampilkan popup, yang akan muncul ketika pengguna menyorot area tertentu.
4. addLegend(): menambahkan legenda
5. addLayersControl(): menampilkan tombol untuk memilih layer yang akan ditampilkan
6. setView(): mengatur posisi dan zooming default