Demonstration code for plotting a graph of world cities along with country borders with the DiagrammeR R package.

world-cities-diagrammer.R

# Installation
#install.packages("devtools")
devtools::install_github("rich-iannone/DiagrammeR")

library(DiagrammeR)

# Create a graph of border coordinates
country_graph <- country_graph()

# Read in a CSV with location and population data for cities all over the world
world_cities <-
  read.csv(system.file("examples/world_cities.csv",
                       package = "DiagrammeR"),
           na.strings = "NANA",
           header = TRUE,
           stringsAsFactors = FALSE)

# Subset the data frame so that only cities with populations greater than
# 500,000 people remain
population_cities <- subset(world_cities, population > 500000)

# Create a node data frame with cities and their coordinates
city_nodes <-
  create_nodes(nodes = 1:nrow(population_cities),
               x = population_cities$longitude * 40,
               y = population_cities$latitude * 40,
               group = population_cities$country_code,
               type = "city",
               shape = "diamond")

# Add random edges between cities
city_edges <-
  create_edges(from = sample(city_nodes$nodes,
                             nrow(population_cities)),
               to = sample(city_nodes$nodes,
                           nrow(population_cities)),
               color = "lightgreen",
               width = 2)

# Make a city graph
city_graph <- create_graph(nodes_df = city_nodes,
                           edges_df = city_edges)

# Combine the city graph with the country graph
combined_graph <- combine_graphs(country_graph, city_graph)

# Render the cities along with the countries
render_graph(combined_graph, output = "visNetwork")