如何使用ggplot2在条形图的条形上方添加边际毯子

Question

是否可以在条形图上方添加边际线？使用以下数据集，如何在巴西上方添加4个边际线，在加拿大上方添加8个边际线，等等。

ctryfees <- feesctry %>% group_by(country) %>% summarise(total = sum(fees))

library(ggplot2)
library(ggthemes)

ggplot(ctryfees, aes(x = country, y = total)) +
  geom_bar(stat = "identity") + theme_tufte() +
  ggtitle("Fees Paid Law Firms per Country\nNumber of Firms Paid\n") +
  labs(x = "", y = "") +
  scale_y_continuous(label = dollar.format) +
  geom_rug(data = feesctry, mapping = aes(x = country, y = firms), sides = "top")

代码在添加了scale_y_continuous这一行之后不起作用，因为它会抛出此错误：Error: Discrete value supplied to continuous scale

> dput(feesctry)
structure(list(country = structure(c(1L, 1L, 1L, 1L, 2L, 3L, 
4L, 4L, 5L, 5L, 6L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 6L, 6L, 3L, 3L, 
3L, 3L), .Label = c("Brazil", "Canada", "China", "France", "Germany", 
"UK"), class = "factor"), firms = structure(c(1L, 2L, 3L, 4L, 
5L, 13L, 18L, 19L, 20L, 21L, 22L, 6L, 7L, 8L, 9L, 10L, 11L, 12L, 
23L, 24L, 14L, 15L, 16L, 17L), .Label = c("brazil1", "brazil2", 
"brazil3", "brazil4", "can1", "can2", "can3", "can4", "can5", 
"can6", "can7", "can8", "china1", "china2", "china3", "china4", 
"china5", "france1", "france2", "german1", "german2", "uk1", 
"uk2", "uk3"), class = "factor"), fees = c(80000, 80000, 80000, 
80000, 1e+05, 5e+05, 2e+05, 2e+05, 1e+05, 1e+05, 5e+05, 1e+05, 
1e+05, 1e+05, 1e+05, 1e+05, 1e+05, 1e+05, 5e+05, 5e+05, 5e+05, 
5e+05, 5e+05, 5e+05)), .Names = c("country", "firms", "fees"), row.names = c(NA, 
-24L), class = "data.frame")

- lawyeR

Answer 1

来自

p <- 
  ggplot(ctryfees, aes(x = country, y = total)) +
  geom_bar(stat = "identity") + theme_tufte() +
  ggtitle("Fees Paid Law Firms per Country\nNumber of Firms Paid\n") +
  labs(x = "", y = "") +
  scale_y_continuous(label = dollar_format()) 

你可以尝试。

p + geom_rug(data = transform(feesctry, id = as.numeric(country)), 
             mapping = aes(x = ave(id, id, FUN = function(x) 
                                                   x + scale(seq_along(x), scale = 50)), 
                           y = 1), 
             sides = "top")

或者只是

p + geom_rug(data = feesctry, 
             mapping = aes(x = jitter(as.numeric(country)), 
                           y = 1), 
             sides = "top")

- lukeA

---

非常好的答案，完全符合我的要求。谢谢。我可以问一下，如果我想使用x = reorder（country，total，mean）以使条形图按总数递增排序，是否应该发布第二个问题？我尝试使用您的代码进行了尝试，但运行标记没有重新排序。 - lawyeR

我会首先使用 ctryfees <- feesctry %>% group_by(country) %>% summarise(total = sum(fees), n = n()) %>% mutate(country = reorder(country, total))，然后再加上 + geom_rug(aes(x = jitter(rep(as.numeric(country), n)), y = 1), sides = "top")。 - lukeA