将管道运算符 %>% 与 colnames()<- 等替换函数一起使用

如何使用管道运算符通过管道输入替换函数，例如colnames()<- ?

这就是我想做的：

library(dplyr)
averages_df <- 
   group_by(mtcars, cyl) %>%
   summarise(mean(disp), mean(hp))
colnames(averages_df) <- c("cyl", "disp_mean", "hp_mean")
averages_df

# Source: local data frame [3 x 3]
# 
#   cyl disp_mean   hp_mean
# 1   4  105.1364  82.63636
# 2   6  183.3143 122.28571
# 3   8  353.1000 209.21429

但理想情况下它会是这样的：

averages_df <- 
  group_by(mtcars, cyl) %>%
  summarise(mean(disp), mean(hp)) %>%
  add_colnames(c("cyl", "disp_mean", "hp_mean"))

有没有一种方法可以做到这一点，而无需每次都编写特殊函数？

这里的答案是一个开始，但不完全是我的问题：dplyr 中的链接算术运算符 https://stackoverflow.com/questions/27364390/chaining-arithmetic-operators-in-dplyr

你可以使用colnames<- or setNames（感谢@大卫·阿伦堡）

group_by(mtcars, cyl) %>%
  summarise(mean(disp), mean(hp)) %>%
  `colnames<-`(c("cyl", "disp_mean", "hp_mean"))
  # or
  # `names<-`(c("cyl", "disp_mean", "hp_mean"))
  # setNames(c("cyl", "disp_mean", "hp_mean")) 

#   cyl disp_mean   hp_mean
# 1   4  105.1364  82.63636
# 2   6  183.3143 122.28571
# 3   8  353.1000 209.21429

或者选择一个Alias (set_colnames) from magrittr:

library(magrittr)
group_by(mtcars, cyl) %>%
  summarise(mean(disp), mean(hp)) %>%
  set_colnames(c("cyl", "disp_mean", "hp_mean"))

dplyr::rename如果您仅（重新）命名许多列中的一些列，可能会更方便（它需要同时写入旧名称和新名称；请参阅@Richard Scriven的答案）