R ggplot legend with Waffle chart-CodePudding

library(tidyverse)
library(waffle)
df_2 <- structure(list(group = c(2, 2, 2, 1, 1, 1), 
  parts = c("A", "B", "C", "A", "B", "C"), 
  values = c(1, 39, 60, 14, 15, 71)), row.names = c(NA,
  -6L), class = c("tbl_df", "tbl", "data.frame"))

df_2 %>% ggplot(aes(label = parts))  
  geom_pictogram(
    n_rows = 10, aes(color = parts, values = values),
    family = "fontawesome-webfont",
    flip = TRUE
  )  
  scale_label_pictogram(
    name = "Case",
    values = c("male"),
    breaks = c("A", "B", "C"),
    labels = c("A", "B", "C")
  )  
  scale_color_manual(
    name = "Case",
    values = c("A" = "red", "B" = "green", "C" = "grey85"),
    breaks = c("A", "B", "C"),
    labels = c("A", "B", "C")
  )  
  facet_grid(~group)

With the above code, I got the legend what I expected:

However, when I replaced df_2 with the following df_1 dataframe, I was unable to combine two legends.

df_1 <- structure(list(group = c(2, 2, 2, 1, 1, 1), 
  parts = c("A", "B", "C", "A", "B", "C"), 
  values = c(0, 0, 100, 0, 0, 100)), 
  row.names = c(NA,-6L), class = c("tbl_df", "tbl", "data.frame"))

I kind of know the cause of the problem (0 values) but I would like to keep the legend the same as the graph above. Any suggestions would be appreciated.

CodePudding user response：

To make it clear, the package "waffle" referred to here is not the CRAN package "waffle", but the GitHub-only package:

remotes::install_github("hrbrmstr/waffle")
library(waffle)

You will also need a way of displaying the pictograms, such as:

library(emojifont)
load.fontawesome()

Now, as with any other discrete scale, if you want to add values that are not present in the (post-stat) data, you need to use the limits argument:

df_1 %>% ggplot(aes(label = parts))  
  geom_pictogram(
    n_rows = 10, aes(color = parts, values = values),
    family = "fontawesome-webfont",
    flip = TRUE
  )  
  scale_label_pictogram(
    name = "Case",
    values = c("male"),
    breaks = c("A", "B", "C"),
    labels = c("A", "B", "C"),
    limits = c("A", "B", "C")
  )  
  scale_color_manual(
    name = "Case",
    values = c("A" = "red", "B" = "green", "C" = "grey85"),
    breaks = c("A", "B", "C"),
    labels = c("A", "B", "C")
  )  
  facet_grid(~group)

CodePudding user response：

It is a bit tricky, but what you could do is say let's add 1 to all values so it will plot it like before. But using ggplot_build to remove from each case one row to get it in the right amount like this:

library(tidyverse)
library(waffle)
library(ggplot2)
library(dplyr)
library(emojifont)
library(waffle)
library(extrafont)

p <- df_1 %>% ggplot(aes(label = parts))  
  geom_pictogram(
    n_rows = 10, aes(color = parts, values = values 1),
    family = "fontawesome-webfont",
    flip = TRUE
  )  
  scale_label_pictogram(
    name = "Case",
    values = c("male"),
    breaks = c("A", "B", "C"),
    labels = c("A", "B", "C")
  )  
  scale_color_manual(
    name = "Case",
    values = c("A" = "red", "B" = "green", "C" = "grey85"),
    breaks = c("A", "B", "C"),
    labels = c("A", "B", "C")
  )  
  facet_grid(~group)

q <- ggplot_build(p)
q$data[[1]] <- q$data[[1]] %>%
  group_by(PANEL) %>%
  slice(4:n())

q <- ggplot_gtable(q)

plot(q)

^{Created on 2022-10-20 with reprex v2.0.2}