原图

image.png

原始代码

# install 'ggalt' pkg
# devtools::install_github("hrbrmstr/ggalt")
options(scipen = 999)
library(ggplot2)
library(ggalt)
midwest_select <- midwest[midwest$poptotal > 350000 & 
                            midwest$poptotal <= 500000 & 
                            midwest$area > 0.01 & 
                            midwest$area < 0.1, ]

# Plot
ggplot(midwest, aes(x=area, y=poptotal)) + 
  geom_point(aes(col=state, size=popdensity)) +   # draw points
  geom_smooth(method="loess", se=F) + 
  xlim(c(0, 0.1)) + 
  ylim(c(0, 500000)) +   # draw smoothing line
  geom_encircle(aes(x=area, y=poptotal), 
                data=midwest_select, 
                color="red", 
                size=2, 
                expand=0.08) +   # encircle
  labs(subtitle="Area Vs Population", 
       y="Population", 
       x="Area", 
       title="Scatterplot + Encircle", 
       caption="Source: midwest")

学习后做的图

image.png

scatterplot with encircling 带有圈 得散点图

图表中列出一些特殊的点或区域，以引起人们对那些特殊情况的注意。

这可以使用ggalt包中的geom_enCircle()方便地完成。

# install.packages('ggalt')
library(ggalt)
ls('package:ggalt')
options(scipen = 999)
library(ggplot2)
library(dplyr)
### select subdata of the dataset 'midwest'
midwest_select=midwest%>%
  filter(poptotal>350000&
           poptotal<=500000&
           area>0.01&
           area<0.1)
#plot
ggplot(data=midwest,aes(x=area,y=poptotal))+
  geom_point(aes(col=state,size=popdensity))+
  geom_smooth(method = 'loess',se=F,formula = 'y~x')+
  geom_encircle(aes(x=area,y=poptotal),
data = midwest_select,
 color="red", 
                size=2, 
                expand=0.08)+
  labs(x='Area',
       y='Population',
       title = 'Scatterplot + Encircle',
       subtitle = 'Area Vs Population',
       caption = 'Source: midwest')+
  xlim(c(0,0.1))+ylim(c(0,500000))+
    theme_bold()+
    theme(plot.caption = element_text(face='bold'))

参考：Top 50 ggplot2 Visualizations - The Master List
其他ggplot2基本语法教程