hierarchical pie

hierarchical pie.R

library(tidyverse)

COUNT = 40

data = tibble(
  car = paste0(sample(LETTERS, COUNT, TRUE), sample(letters, COUNT, TRUE), sample(letters, COUNT, TRUE)),
  value = rnorm(COUNT, 3),
  group = c(rep("Petrol", COUNT/2), rep("Hybrid", COUNT/4), rep("Pure Electric", COUNT/8), rep("Diesel", COUNT/8))
)

data = data %>% 
  arrange(group, value) %>% 
  mutate(isOdd = rep(c(T,F), COUNT/2)) %>% 
  mutate(y_start = c(0, lag(cumsum(value))[-1]))

ggplot(data) +
  aes(ymin=y_start, ymax=y_start+value, fill=group, color=group, alpha = isOdd) +
  geom_rect(alpha=1, xmin=0, xmax=1) +
  geom_rect(color=NA, fill="white", xmin=.7, xmax=1) +
  geom_text(aes(label=car, y=y_start+value/2), x=.8, color="white", alpha=.75) +
  scale_alpha_manual(values = c(0, 0.25)) +
  scale_color_manual(values = c("#183263", "#244D8B", "#008001", "black")) +
  scale_fill_manual(values = c("#183263", "#244D8B", "#008001", "black")) +
  coord_polar("y", start=0) +
  theme_void()