Is there an R function to normalize height in a pie chart?

Question

I'm trying to compare two pie chart from ggplot2,but when I try to graph it because of the big difference in length of the dataset It look very small.

I wanted the piechart divided by a category and group by another.

df %>% 
  count(category,group) %>% 
  ggplot(aes(x="", y=n, fill=factor(group))) +
  geom_bar(stat="identity", width=1)  +
  coord_polar("y", start=0) +
  facet_wrap(~category) 

I did the following to normalize their height.

Piechartdf <- df %>% 
  count(category,group) 

Piechart <- Piechart %>%
      mutate(proportion = case_when(
        Type=="category1" ~ n/sum(Piechart[which(Piechart$Type == "category1"), 3]),
        Type=="category2" ~ n/sum(Piechart[which(Piechart$Type == "category2"), 3])
      ))

Then in the first one, I just chance n for proportion, Is there an easier way to achieve this?

Answer 1

You may try

df %>% 
  count(category,group) %>%
  group_by(category) %>%
  mutate(n = n/sum(n)) %>%
  ggplot(aes(x="", y=n, fill=factor(group), group = category)) +
  geom_bar(stat="identity", width=1)+
  coord_polar("y", start=0)  +
  facet_wrap(~category)