choropleth map of Japan

nuriwake_chizu.R

nuriwake_chizu <-function(d,pal.name="Oranges"){
  n.FD <-nclass.FD(d)
  n.bins <-min(n.FD,9)
  colclass=cut(d,seq(min(d),max(d),length.out = n.bins+1),include.lowest = TRUE,dig.lab = 2)
  col_ <-RColorBrewer::brewer.pal(n.bins,name=pal.name)
  col_tab <-data.frame(class=factor(levels(colclass)),col=col_,stringsAsFactors = FALSE)
  outcol <-merge(data.frame(id=1:47,class=colclass),col_tab,by="class")
  outcol <- outcol[order(outcol$id),]
  old_par =par(no.readonly = TRUE)
  par(mai=c(0,0,0,0))
  p = NipponMap::JapanPrefMap(col=outcol$col)
  legend("bottomright",legend=col_tab$class,fill=col_tab$col,bty = "n")
  par(old_par)
  invisible(p)
}