Merging legends in plotly subplot

Dan Опубликовано в Dev

dan

I have several groups where for each I have several classes for which I measured continuous values:

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"))

Not each group in the data has the same classes, or put differently each group has a subset of all classes.

I'm trying to generate R plotly density curves for each group, color-coded by class, and then combine them all to a single plot using plotly's subplot function.

This is what I'm doing:

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)

Which gives:

The problems I'd like to fix are:

Have the legend appear only once (right now it repeats for each group) merging all classes
Have the title appear in each of the subplots rather than only for the last plot at is it is now. (I know that I could simply have the group name as the x-axis titles but I'd rather save that space because in reality I have more than 3 groups)

Bappa Das

You can use the following code

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')
)

which gives me the following plot