基本简介
面积图（Area chart）结合了折线图和条形图，以显示一个或多个组的数值如何随第二个变量（通常是时间）的变化而变化。面积图与折线图的区别在于在线和基线之间增加了阴影，就像条形图一样。在R中，可以用ggplot2包的geom_area()函数进行绘制。
示例代码
#调用需要的R包
library(ggplot2)
library(dplyr)
#创建数据集
time <- as.numeric(rep(seq(1,7),each=7)) # x Axis
value <- runif(49, 10, 100) # y Axis
group <- rep(LETTERS[1:7],times=7) # group, one shape per group
data <- data.frame(time, value, group)
#查看数据集(前6行)
head(data)
# 绘制基本的面积图(堆叠)
ggplot(data, aes(x=time, y=value, fill=group)) +
geom_area()
#
# 设置group的顺序
data$group <- factor(data$group , levels=c("B", "A", "D", "E", "G", "F", "C") )
# 绘图
ggplot(data, aes(x=time, y=value, fill=group)) +
geom_area()
#计算百分比(dplyr包)
library(dplyr)
data <- data %>%
group_by(time, group) %>%
summarise(n = sum(value)) %>%
mutate(percentage = n / sum(n))
# 设置group的顺序
data$group <- factor(data$group , levels=c("B", "A", "D", "E", "G", "F", "C") )
# 绘图
ggplot(data, aes(x=time, y=percentage, fill=group)) +
geom_area(alpha=0.6 , size=1, colour="black")
参考文献
[1] https://r-graph-gallery.com/index.html
[2] https://www.modb.pro/db/509252
[3] https://www.data-to-viz.com/graph/stackedarea.html#:~:text=A%20stacked%20area%20chart%20is%20the%20extension%20of,numeric%20variable%2C%20and%20the%20importance%20of%20each%20group.
