我们希望在R中重命名数据帧中的列，但是这些列可能会丢失，这会引发一个错误:
my_df <- data.frame(a = c(1,2,3), b = c(4,5,6))
my_df %>% dplyr::rename(aa = a, bb = b, cc = c)
Error: Can't rename columns that don't exist.
x Column `c` doesn't exist.
我们想要的输出是这样的，如果原始列不存在，它将创建一个带有NA值的新列:
> my_df
aa bb c
1 1 4 NA
2 2 5 NA
3 3 6 NA
一个可能的解决方案:
library(tidyverse)
my_df <- data.frame(a = c(1,2,3), b = c(4,5,6))
cols <- c(a = NA_real_, b = NA_real_, c = NA_real_)
my_df %>% add_column(!!!cols[!names(cols) %in% names(.)]) %>%
rename(aa = a, bb = b, cc = c)
#> aa bb cc
#> 1 1 4 NA
#> 2 2 5 NA
#> 3 3 6 NA