如何向R中的地图添加列(基于圆圈的大小)？

install.packages("ggplot2")

library(ggplot2)

map <- ggplot(data = worldmap)

map <- map + geom_polygon(aes(x = long, y = lat, group = group), fill = "white", color = "black")

map <- map + geom_point(aes(x = longitude, y = latitude, size = size))

map <- map + scale_size_continuous(range = c(1, 10))

library(ggplot2)

# 创建地图对象
map <- ggplot(data = worldmap)

# 添加地图边界
map <- map + geom_polygon(aes(x = long, y = lat, group = group), fill = "white", color = "black")

# 添加圆圈的大小
map <- map + geom_point(aes(x = longitude, y = latitude, size = size))

# 调整圆圈的大小范围
map <- map + scale_size_continuous(range = c(1, 10))

# 显示地图
print(map)