r - top_n() 没有选择 n

Question

目的:按降序绘制前 20 个国家

问题:当使用top_n函数时，它坚持选择所有而不仅仅是前20名。

这是我的代码:

#Omit missing values
na.omit(kiva_loans)%>%
  #Group by country label
  group_by(country_code)%>%
  dplyr::count(country_code, sort = TRUE)%>%
  top_n(20)%>%
   ggplot(aes(reorder(x=country_code,n),y=n))+
   geom_col(position="dodge",
            color = "black",
            fill="purple")+
   coord_flip()

在 top_n(20) 行之后，输出为:

这表明它不会在 20 时停止。这又是可怕的情节:

Answer 1

#Omit missing values
na.omit(kiva_loans)%>%
  #Group by country label
  group_by(country_code)%>%
  dplyr::count(country_code, sort = TRUE)%>%
  ungroup() %>% # add this to ungroup
  top_n(20)%>%
   ggplot(aes(reorder(x=country_code,n),y=n))+
   geom_col(position="dodge",
            color = "black",
            fill="purple")+
   coord_flip()

在调用top_n之前只需ungroup()

从 ?top_n 你可以读到:

n number of rows to return. If x is grouped, this is the number of rows per group. Will include more than n rows if there are ties.