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rlegendwaffle-chart

How do I add text in the legend section of a waffle plot in R?

I am trying to create a waffle plot. My data and waffle plot looked like this-

library(waffle)
parts=c("Extraction"=397, "Operculectomy"=11, "Medication"=3)
waffle(parts, row=12, colors=c("#CC0000", "#006600", "#669999"))

enter image description here

I want to add some text on the label of the legend section of this plot like below:

Extraction (397/413)

Operculectomy (11/413)

Medication (3/413)

Solution

  • Based on the documentation of the waffle package, I'm not sure you can set a lot of parameters to your waffle plots.

    However, you can modify category names of your data before by doing:

    library(waffle)
parts=c("Extraction"=397, "Operculectomy"=11, "Medication"=3)
names(parts) = paste0(names(parts),"(",parts,"/",sum(parts),")")
waffle(parts, row=12, colors=c("#CC0000", "#006600", "#669999"))

    Which gives you the following graph: enter image description here

    Alternative using ggplot2

    Alternatively you can do a "waffle" plot by using geom_tile from ggplot2. The procedure is a little bit less straightforward but at least you can enjoy the full customization tools of ggplot2. To get the same graph, you can do:

    library(ggplot2)
categ_table = c("Extraction"=397, "Operculectomy"=11, "Medication"=3)
df <- expand.grid(y = 1:10, x = 1:(round(sum(categ_table)/10)+1))
df$Category = factor(c(rep(names(categ_table),categ_table),rep(NA,nrow(df)-sum(categ_table))))
df = df[!is.na(df$Category),]

ggplot(df, aes(x = x, y = y, fill = Category)) + 
  geom_tile(color = "white", size = 0.5) +
  scale_x_continuous(expand = c(0, 0)) +
  scale_y_continuous(expand = c(0, 0))+
  theme(legend.title = element_blank(),
        panel.background = element_rect(fill = 'white', colour = 'white'),
        axis.text = element_blank(),
        axis.title = element_blank(),
        axis.ticks = element_blank())+ 
  scale_fill_manual(values = c("#CC0000", "#006600", "#669999"),
                    breaks = names(categ_table), 
                    labels = c("Extraction (397/411)","Operculectomy (11/411)", "Medication (3/411)"))

    And you get the following graph: enter image description here

    Hope it answers your question