Adding percentage labels on pie chart in R

Question

My data frame looks like

df
   Group   value
1 Positive    52
2 Negative   239
3 Neutral     9

I would like to make a pie chart of the dat

Answer 1

Here is an idea matching the order of groups in the pie chart and the order of labels. I sorted the data in descending order by value. I also calculated the percentage in advance. When I drew the ggplot figure, I specified the order of Group in the order in mydf (i.e., Negative, Positive, and Neutral) using fct_inorder(). When geom_label_repel() added labels to the pie, the order of label was identical to that of the pie.

library(dplyr)
library(ggplot2)
library(ggrepel)
library(forcats)
library(scales)

mydf %>%
arrange(desc(value)) %>%
mutate(prop = percent(value / sum(value))) -> mydf 

pie <- ggplot(mydf, aes(x = "", y = value, fill = fct_inorder(Group))) +
       geom_bar(width = 1, stat = "identity") +
       coord_polar("y", start = 0) +
       geom_label_repel(aes(label = prop), size=5, show.legend = F, nudge_x = 1) +
       guides(fill = guide_legend(title = "Group"))

DATA

mydf <- structure(list(Group = structure(c(3L, 1L, 2L), .Label = c("Negative", 
"Neutral", "Positive"), class = "factor"), value = c(52L, 239L, 
9L)), .Names = c("Group", "value"), class = "data.frame", row.names = c("1", 
"2", "3"))