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rggplot2ggforce

Draw three-quarter-circle in `ggplot2` with arrow and label


I want to draw three-quarter-circles in ggplot2 with arrows and labels. Using ggplot2 and ggforce I found something that works, but it seems utterly complicated.

Are there simpler options to achieve what I want?


df <- data.frame(x = 100, y = 100, label = "R")

library(ggplot2)
library(ggforce)

r <- 10

ggplot(df) + 
  geom_circle(aes(x0 = x, y0 = y, r = r)) +
  geom_rect(aes(xmin = x, ymin = y, xmax = x + r + 1, ymax = x + r + 1), 
            fill = "white") +
  geom_segment(aes(x = x + r, y = y, xend = x + r, yend = y + 1), 
               arrow = arrow()) +
  annotate("text", x = df$x, y = df$y, label = df$label) + 
  theme_void()

enter image description here


Solution

  • Would this be considered simpler?

    ggplot(df) + 
      geom_arc(aes(x0 = x, y0 = y, r = r,
                   start = 0, end = -1.5 * pi),
               arrow = arrow()) + 
      annotate("text", x = df$x, y = df$y, label = df$label) + 
      theme_void()
    
    # equivalent to above with geom_text instead; I'm not sure if your actual use
    # case has preference for one or the other
    ggplot(df) + 
      geom_arc(aes(x0 = x, y0 = y, r = r,
                   start = 0, end = -1.5 * pi),
               arrow = arrow()) + 
      geom_text(aes(x = x, y = y, label = label)) + 
      theme_void()
    

    plot