r - 向 ggalt::geom_dumbbell 图添加图例并对 y 轴进行排序

Question

在 this SO answer , 用户@Crops 展示了如何向 ggalt::geom_dumbbell 添加图例阴谋。非常好。

library(ggalt)

df <- data.frame(trt=LETTERS[1:5], l=c(20, 40, 10, 30, 50), r=c(70, 50, 30, 60, 80))
df2 = tidyr::gather(df, group, value, -trt)

ggplot(df, aes(y = trt)) + 
     geom_point(data = df2, aes(x = value, color = group), size = 3) +
     geom_dumbbell(aes(x = l, xend = r), size=3, color="#e3e2e1", 
                   colour_x = "red", colour_xend = "blue",
                   dot_guide=TRUE, dot_guide_size=0.25) +
     theme_bw() +
     scale_color_manual(name = "", values = c("red", "blue") )

我要排序 trt下降在 r .我尝试更换 y = trt与 y = reorder(trt, r) ，但我收到一个错误，对象 r没有找到。

Answer 1

这是我们重新排序 trt 的因子水平的方法在 df和 df2在我们绘图之前。

# reorder factor levels
df$trt <- reorder(df$trt, df$r)
df2$trt <- factor(df2$trt, levels = levels(df$trt))

ggplot(df, aes(y = trt)) + 
  geom_point(data = df2, aes(x = value, color = group), size = 3) +
  geom_dumbbell(aes(x = l, xend = r), size=3, color="#e3e2e1", 
                colour_x = "red", colour_xend = "blue",
                dot_guide=TRUE, dot_guide_size=0.25) +
  theme_bw() +
  scale_color_manual(name = "", values = c("red", "blue") )