joke_map.R

joke_map.R

joke_map <- function(states_to_highlight, title="", highlight_colors=c("#aaaaaa", "#ee0000")) {
  library(dplyr)
  library(ggplot2)
  library(RColorBrewer)
  library(maps)
  
  highlighting = data.frame(region=tolower(state.name[match(states_to_highlight, state.abb)]), 
                             highlight=TRUE)
  
  d = map_data("state") %>% left_join(highlighting, by="region")
  d[is.na(d$highlight),]$highlight <- FALSE

  p <- ggplot(d) + geom_polygon(aes(x=long, y=lat, 
                                   group = group, fill=highlight), 
                               colour="black") + 
    scale_fill_manual(values=highlight_colors) + 
    ggtitle(title) + 
    xlab("") +
    ylab("") +
    theme(axis.ticks = element_blank(), axis.text.x = element_blank(), axis.text.y = element_blank()) +
    guides(fill=FALSE)
  
  p
}