在情节次要情节中合并图例

Question

我有几个组，每个组有几个类，我测量了连续值：

set.seed(1)

df <- data.frame(value = c(rnorm(100,1,1), rnorm(100,2,1), rnorm(100,3,1),
                           rnorm(100,3,1), rnorm(100,1,1), rnorm(100,2,1),
                           rnorm(100,2,1), rnorm(100,3,1), rnorm(100,1,1)),
                 class = c(rep("c1",100), rep("c2",100), rep("c3",100),
                           rep("c2",100), rep("c4",100), rep("c1",100),
                           rep("c4",100), rep("c3",100), rep("c2",100)),
                 group = c(rep("g1",300), rep("g2",300), rep("g3",300)))

df$class <- factor(df$class, levels =c("c1","c2","c3","c4"))
df$group <- factor(df$group, levels =c("g1","g2","g3"))

并非数据中的每个组都具有相同的类，或者换句话说，每个组都具有所有类的子集。

我试图R plotly为每个组生成密度曲线，按类别进行颜色编码，然后使用plotlyssubplot函数将它们全部组合成一个图。

这就是我正在做的：

library(dplyr)
library(ggplot2)
library(plotly)


set.seed(1)

df <- data.frame(value = c(rnorm(100,1,1), rnorm(100,2,1), rnorm(100,3,1),
                           rnorm(100,3,1), rnorm(100,1,1), rnorm(100,2,1),
                           rnorm(100,2,1), rnorm(100,3,1), rnorm(100,1,1)),
                 class = c(rep("c1",100), rep("c2",100), rep("c3",100),
                           rep("c2",100), rep("c4",100), rep("c1",100),
                           rep("c4",100), rep("c3",100), rep("c2",100)),
                 group = c(rep("g1",300), rep("g2",300), rep("g3",300)))

df$class <- factor(df$class, levels =c("c1","c2","c3","c4"))
df$group <- factor(df$group, levels =c("g1","g2","g3"))

plot.list <- lapply(c("g1","g2","g3"), function(g){
  density.df <- do.call(rbind,lapply(unique(dplyr::filter(df, group == g)$class),function(l)
    ggplot_build(ggplot(dplyr::filter(df, group == g & class == l),aes(x=value))+geom_density(adjust=1,colour="#A9A9A9"))$data[[1]] %>%
      dplyr::select(x,y) %>% dplyr::mutate(class = l)))
  plot_ly(x = density.df$x, y = density.df$y, type = 'scatter', mode = 'lines',color = density.df$class) %>%
    layout(title=g,xaxis = list(zeroline = F), yaxis = list(zeroline = F))
})
subplot(plot.list,nrows=length(plot.list),shareX=T)

这使：

我想解决的问题是：

1. 让图例仅出现一次（现在每个组重复）合并所有类
2. 让标题出现在每个子图中，而不是仅出现在最后一个图上。（我知道我可以简单地将组名称作为 x 轴标题，但我宁愿节省该空间，因为实际上我有超过 3 个组）

Answer 1

您可以使用以下代码

library(tidyverse)
library(plotly)

ggplotly(
  ggplot(df, aes(x=value, col = class)) + 
  geom_density(adjust=1) + 
  facet_wrap(~group, ncol = 1) +
    theme_minimal() + 
    theme(legend.position = 'top')
)

这给了我以下情节