Map of women's suffrage in Europe #DataIsBeautiful #1

plot_map.R

library(ggplot2)
library(grid)
library(rworldmap)
library(grid)

# Data sources:

# https://en.wikipedia.org/wiki/Timeline_of_women%27s_suffrage
# http://womensuffrage.org/?page_id=97

# Get the world map
worldMap <- getMap()

# Member States of the European Union
europeanUnion <- c("Austria", "Belgium", "Bulgaria", "Croatia", "Cyprus",
                   "Czech Rep.", "Denmark", "Estonia", "Finland", "France",
                   "Germany", "Greece", "Hungary", "Ireland", "Italy", "Latvia",
                   "Lithuania", "Luxembourg", "Malta", "Netherlands", "Poland",
                   "Portugal", "Romania", "Slovakia", "Slovenia", "Spain",
                   "Sweden", "United Kingdom")

europeanUnion <- c(europeanUnion, 'Belarus', 'Ukraine', 'Switzerland', 
                   'Moldova', 'San Marino', 'Albania', 'Macedonia', 'Turkey', 
                   'Norway', 'Georgia', 'Armenia', 'Russia', 'Iceland')

# Select only the index of states member of the E.U.
idxEurope <- which(worldMap$REGION == 'Europe')

europeanDataTable <- data.frame(country = europeanUnion, value = c('1918', '1948', '1944', '1945', '1960',
                                                                   '1920', '1915', '1917', '1906', '1945',
                                                                   '1918', '1952', '1945', '1928', '1945', 
                                                                   '1905', '1917', '1919', '1947', '1919', '1918',
                                                                   '1976', '1946', '1920', '1945', '1931', 
                                                                   '1921', '1928', '1917', '1917', '1990',
                                                                   '1918', '1973', '1920', '1946', '1934', 
                                                                   '1913', '1919', '1917', '1917', '1915'), 
                                stringsAsFactors=FALSE)

europeanDataTable$value <- as.numeric(europeanDataTable$value)

# Extract longitude and latitude border's coordinates of members states of E.U. 
europeCoords <- lapply(idxEurope, function(i){
  df <- data.frame(worldMap@polygons[[i]]@Polygons[[1]]@coords)
  df$region =as.character(worldMap$NAME[i])
  colnames(df) <- list("long", "lat", "region")
  return(df)
})

europeCoords <- do.call("rbind", europeCoords)

europeCoords$value <- europeanDataTable$value[match(europeCoords$region, europeanDataTable$country)]

# Plot the map
P <- ggplot() + geom_polygon(data = europeCoords, aes(x = long, y = lat, group = region, fill = value),
                             colour = "black", size = 0.1) +
  coord_map(xlim = c(-13, 47),  ylim = c(34, 71))

P <- P + scale_fill_gradient2(breaks = seq(1900, 2000, 10), name = "Year of introducing full suffrage", 
                             low = "skyblue1", mid="mediumblue", midpoint=1950, high = "navyblue", 
                             na.value = "grey50")

P <- P + theme(#panel.grid.minor = element_line(colour = NA), panel.grid.minor = element_line(colour = NA),
  panel.background = element_rect(fill = NA, colour = NA),
  axis.text.x = element_blank(),
  legend.key.size = unit(3.5, 'lines'),  # 3.5 for export to png, width is 1600
  axis.text.y = element_blank(), axis.ticks.x = element_blank(),
  axis.ticks.y = element_blank(), axis.title = element_blank(),
  #rect = element_blank(),
  plot.margin = unit(0 * c(-1.5, -1.5, -1.5, -1.5), "lines"))

P