【Visualization】饼图，一网打尽！（中）

ggplot绘制饼图

ggplot, facet, piechart: placing text in the middle of pie chart slices

基本饼图并添加数字

dat = read.table(text = "Channel Volume Cnt
AGENT   high   8344
AGENT medium   5448
AGENT    low  23823
KIOSK   high  19275
KIOSK medium  13554
KIOSK    low  38293", header=TRUE)


ggplot(data = dat, aes(x = 0, y = Cnt, fill = Volume)) + 
  geom_bar(stat = "identity") +
  geom_text(aes(label = Cnt), position = position_stack(vjust = 0.5)) +
  scale_x_continuous(expand = c(0,0)) +
  coord_polar(theta = "y") +
  facet_wrap(Channel ~ .)

因为两个列总和不等，因此会出现一个pie图不完全（无法通过设置scale='free'解决，因为会报错），

解决：（只对facet_wrap有用）

Awkward interaction between faceting, polar coordinates, and free scales

cp <- coord_polar(theta = "y")
cp$is_free <- function() TRUE
ggplot(data = dat, aes(x = 0, y = Cnt, fill = Volume)) + 
  geom_bar(stat = "identity") +
  geom_text(aes(label = Cnt), position = position_stack(vjust = 0.5)) +
  scale_x_continuous(expand = c(0,0)) +
  cp+
  facet_wrap(Channel ~ ., scales = "free")

中间空心的饼图

## 方法一：扩大x轴的范围：lims(x = c(-1, 0.5))
## tips：扩大范围的需要根据不同的数据集修改，下限扩大越多，空心部分越大，上限扩大越多，整个饼图在画布的占比越小
cp <- coord_polar(theta = "y")
cp$is_free <- function() TRUE
ggplot(data = dat, aes(x = 0, y = Cnt, fill = Volume)) + 
  geom_bar(stat = "identity") +
  geom_text(aes(label = Cnt), position = position_stack(vjust = 0.5)) +
  cp+
  lims(x = c(-1,0.5)) + 
  facet_wrap(Channel ~ ., scales = "free")

## 方法二：再添加一条bar
## tips:新加列的x轴位置越低，空心越大，x轴位置不能低于原图图形x轴下限，否则不会造成空心
cp <- coord_polar(theta = "y")
cp$is_free <- function() TRUE
ggplot(data = dat, aes(x = 0, y = Cnt, fill = Volume)) + 
  geom_bar(stat = "identity") +
  geom_text(aes(label = Cnt), position = position_stack(vjust = 0.5)) +
  cp+
  geom_col(aes(x=-1,y=0))+
  facet_wrap(Channel ~ ., scales = "free")

添加比例

## 使用geom_text
cp <- coord_polar(theta = "y")
cp$is_free <- function() TRUE
ggplot(data = dat, aes(x = 0, y = Cnt, fill = Volume)) + 
  geom_bar(stat = "identity") +
  geom_text(aes(label = scales::percent(Cnt/sum(Cnt))), position = position_stack(vjust = 0.5)) +
  cp+
  geom_col(aes(x=-1,y=0))+
  facet_wrap(Channel ~ ., scales = "free")

添加文本和比例

## 使用geom_text
cp <- coord_polar(theta = "y")
cp$is_free <- function() TRUE
ggplot(data = dat, aes(x = 0, y = Cnt, fill = Volume)) + 
  geom_bar(stat = "identity") +
  geom_text(aes(label = paste0(Channel,'\n',Volume ,'\n',scales::percent(Cnt/sum(Cnt)))), position = position_stack(vjust = 0.5)) +
  cp+
  geom_col(aes(x=-1,y=0))+
  facet_wrap(Channel ~ ., scales = "free")

中间有两个圈的饼图

cp <- coord_polar(theta = "y")
cp$is_free <- function() TRUE
ggplot(data = dat, aes(x = Channel, y = Cnt, fill = Volume)) + 
  geom_bar(stat = "identity") +
  geom_text(aes(label = paste0(Channel,'\n',Volume ,'\n',scales::percent(Cnt/sum(Cnt)))), position = position_stack(vjust = 0.5)) +
  cp+
  geom_col(aes(x=-0.5,y=0))+
  facet_wrap(. ~ ., scales = "free")

## 换一个数据集，中间能对齐的两个圈
pie_data <- data.frame(category=c('A','B','C','A','B','C'),
                       year=c(2020,2020,2020,2021,2021,2021),
                       sales=c(40,30,20,20,30,40))
ggplot(data=pie_data,aes(x=factor(year),y=sales,fill=category))+
  geom_col(width=1,color='white')+
  geom_text(aes(label = scales::percent(sales/sum(sales))), position = position_stack(vjust = 0.5)) +
  coord_polar(theta = 'y')+
  geom_col(aes(x=0,y=0))+
  theme_void()

ggpubr绘制饼图

Plotting Pie and Donut Chart with ggpubr pckage in R

Donut chart

与ggplot2类似，这里介绍下空心饼图与实心饼图拼图

pie_data <- data.frame(category=c('A','B','C','A','B','C'),
                       year=c(2020,2020,2020,2021,2021,2021),
                       sales=c(40,30,20,20,30,40))