原文链接：http://tecdat.cn/?p=13247
本文我们绘制英国脱欧投票的地图。第一步是绘制底图
代码语言：javascript复制library(sp)library(raster)download.file("http://biogeo.ucdavis.edu/data/gadm2.8/rds/GBR_adm2.rds","GBR_adm2.rds")UK=readRDS("GBR_adm2.rds")UK@data[159,"HASC_2"]="GB.NR"plot(UK, xlim = c(-4,-2), ylim = c(50, 59), main="UK areas")
添加爱尔兰
代码语言：javascript复制plot(IRL,add=TRUE)
添加法国，它位于右下方，因此我们应该看到一点…
代码语言：javascript复制plot(FR,add=TRUE)
然后，我们可以检索英国退欧公投数据
代码语言：javascript复制referendum=ddply(referendum,.(Region,HASC_code),summarise,Remain=sum(Remain),Leave=sum(Leave))我们可以发现，脱欧赢得了51.89％的选票
代码语言：javascript复制> sum(referendum$Leave)/(sum(referendum$Leave) sum(referendum$Remain))[1] 0.5189184大家可以看一下，使用
代码语言：javascript复制plot(UK, col = map_data$Brexit, border = "gray1", xlim = c(-4,-2), ylim = c(50, 59), main="How the UK has voted?", bg="#A6CAE0")plot(IRL, col = "lightgrey", border = "gray1",add=TRUE)plot(FR, col = "lightgrey", border = "gray1",add=TRUE)
（我们添加了一个小图例以使其更清晰）。为此，我们可以使用制图软件包
代码语言：javascript复制plot(UK, col = "grey", border = "gray1", xlim = c(-4,-2), ylim = c(50, 59),bg="#A6CAE0")plot(IRL, col = "lightgrey", border = "gray1",add=TRUE)plot(FR, col = "lightgrey", border = "gray1",add=TRUE)choroLayer(spdf = UK,df = map_data,var = "Percentage_Remain",breaks = seq(0,100,10),col = cols,legend.pos = "topright",legend.title.txt = "",legend.values.rnd = 2,add = TRUE)
