library(maps)
library(mapdata)
library(ggplot2)
china_map <- map_data("china")
ggplot() +
geom_polygon(data = china_map, aes(x = long, y = lat, group = group), fill = "white", colour = alpha("black", 0.9)) +
geom_point(data = data, aes(x = V1, y = V2)) +
coord_fixed() +
labs(x = "经度", y = "纬度")
