r - 向 ggplot violinplot 图例添加“样本大小”时出现问题

Question

我有以下 ggplot2 violinplot

library(ggplot2)                                                                                                                                                                                                                                                                                                      
bp <- ggplot(data=PlantGrowth, aes(x=group, y=weight, fill=group)) + 
             geom_violin() +
             geom_dotplot(binaxis='y', stackdir='center', dotsize=0.5, binwidth = 0.01)                      

根据前面的示例，我不清楚如何在图例中放置标签（如 所示vplot()。我想在图例中每个标签的右侧放置一个整数

ctrl 10
trt1 10
trt2 10

我已经手动计算了这些

> table(PlantGrowth$group) 

自动执行此操作的标准方法是什么？我试过这个功能

give.sample.size <- function(x) {                                                                                                                                                                                                                                                                                                
    return(c(y = mean(x), label = length(x)))                                                                                                                                                                                                                                                                         
}                                                                                                                                                                                                                                                                                                                 


bp <- ggplot(data=PlantGrowth, aes(x=group, y=weight, fill=group)) +
   geom_violin() + 
   geom_dotplot(binaxis='y', stackdir='center', dotsize=0.5, binwidth = 0.01) + 
   stat_summary(fun.data = give.sample.size, geom = "text")

但这不会影响传奇。

Answer 1

以下解决方案是对您的代码稍作修改。我所做的只是通过制作新标签 ( PlantGrowth %>% group_by(group) %>% mutate(group2=paste(group,length(group))) %>% ungroup()) 来更改数据集并将新标签用作图例 ( fill=group2)。

require(dplyr)
require(ggplot2)
bp <- ggplot(data=PlantGrowth %>% group_by(group) %>% mutate(group2=paste(group,length(group))) %>% 
ungroup(), aes(x=group, y=weight, fill=group2)) + geom_violin() +
geom_dotplot(binaxis='y', stackdir='center', dotsize=0.5, binwidth = 0.01) + 
stat_summary(fun.data = give.sample.size, geom = "text")