最近有小伙伴让在出几篇关于地图绘制的教程,观众老爷的需求这个当然要满足;今天继续来介绍ggplot2绘制地图,同样的操作不同的感觉,下面将详细介绍如何绘制下图

1.安装加载R包
package.list=c("tidyverse","cowplot","ggspatial","ggsci")
for (package in package.list) {
if (!require(package,character.only=T, quietly=T)) {
install.packages(package)
library(package, character.only=T)
}
}
2.构建世界地图数据集
world_map <- map_data("world") %>% dplyr::rename(country=region) %>%
mutate(country=str_replace(country,"Taiwan","China")) %>%
filter(country != "Antarctica") # 剔除南极洲数据
3.构建需要展示的国家数据
map <- c("Australia","China","Denmark","Finland","South Africa",
"France","Germany","Russia","Egypt",
"Hungary","Japan","Brazil","UK","USA","Canada") %>%
as.data.frame() %>% dplyr::rename(country=".") %>%
mutate(country=str_replace(country,"Korea","South Korea")) %>%
mutate(cou=country)
4.绘制世界地图
p1 <- world_map %>% left_join(.,map,by="country") %>%
ggplot()+
geom_polygon(aes(x = long, y = lat,group = group,fill = cou),
color = "black",size = 0.2,show.legend = F)+
scale_fill_simpsons(na.value="gray70")+ # 将无需显示的国家设置为灰色
theme_void()+
theme(plot.background = element_rect(fill="#3ED5F7",
color="#3ED5F7",size = 1))+
annotation_north_arrow(location = "bl",pad_x = unit(0.2,"in"),
pad_y = unit(6,"in"),
style = north_arrow_nautical(fill = c("grey40","white"),
line_col = "grey20")) # 添加指北针
p1

5.构建欧洲主要国家数据集
data <- world_map %>%
filter(.,country %in% c("Austria","Belgium","Bulgaria","Croatia","Cyprus",
"Czech Rep.","Denmark","Estonia","Finland","France",
"Germany","Greece","Hungary","Ireland","Italy","Latvia",
"Lithuania","Luxembourg","Malta","Netherlands","Poland",
"Portugal","Romania","Slovakia","Slovenia","Spain",
"Sweden","UK"))
6.构建国家标签
label <- data %>%
filter(.,country %in% c("Denmark","Estonia","Finland","France",
"Germany","Sweden","UK")) %>%
group_by(country) %>%
summarise(long = mean(long), lat = mean(lat))
7.绘制欧洲地图
p2 <- data %>% ggplot()+
geom_polygon(aes(x = long, y = lat,group = group,fill = country),
color = "black",size = 0.2,show.legend = F)+
geom_text(data =label,aes(long,lat,label=country),size =3, hjust = 0.5)+ # 添加国家名称
scale_fill_manual(values= colorRampPalette(brewer.pal(8,"Set2"))(27))+
theme_void()+
theme(plot.background = element_rect(fill="#3ED5F7",color="black",size=0.8))
p2

8.拼图
ggdraw(p1) + draw_plot(p2,x=-0.355,y=-0.35,scale=.315)

喜欢的小伙伴欢迎关注我的公众号
R语言数据分析指南,持续分享数据可视化的经典案例及一些生信知识,希望对大家有所帮助
网友评论