R/corona_map.r

In pkuhnert/mapcorona: Mapping the spread of the corona virus

#' corona_map
#' 
#' @param d date to extract
#' @param corona_m data frame with corona virus cases
#' @param world  world map
#' 
#' @importFrom grDevices heat.colors
#' 
#' @export

corona_map <- function(d, corona_m, world){
  
  corona_extract <- corona_m[corona_m$date == d,]
  m_extract <- match(corona_extract$location, world$geounit)
  corona <- rep(NA, length(world$geounit))
  corona[m_extract] <- corona_extract$total_cases
  corona <- corona/(world$pop_est/1000000)
 

 corona[is.na(corona)] <- 0
 coronaC <- cut(corona, 
                breaks = c(0, 0.000001, 1, 10, 40, 100, 500, 1000, 10000), 
                include.lowest = TRUE)

  levels(coronaC) <- c("Not Reported", "<1", "1-10", "11-40", "41-100",
                             "101-500", "501-1000", ">1000")
  world[,"coronaC"] <- coronaC

  cols <- c("white", rev(heat.colors(7)))
  
  # Binned
  gworld <- ggplot(data = world) +
    geom_sf(aes(fill = coronaC)) + 
    labs(fill = "Cumulative number of \n COVID-19 cases per million") +
    scale_fill_manual(values  = cols, drop = FALSE) +
    guides(fill = guide_legend(reverse = TRUE)) +
    ggtitle(d) + theme(plot.title = element_text(size=22))
  

  gworld
  
}