R dplyr - 在所有列中都不同

Question

有没有办法指定 dplyr::distinct 应该使用所有列名而不诉诸非标准评估？

df <- data.frame(a=c(1,1,2),b=c(1,1,3))

df %>% distinct(a,b,.keep_all=FALSE)          # behavior I'd like to replicate

对比

df %>% distinct(everything(),.keep_all=FALSE) # with syntax of this form

Answer 1

您可以使用以下代码区分所有列。

library(dplyr)
library(data.table)

df <- data_frame(
  id = c(1, 1, 2, 2, 3, 3),
  value = c("a", "a", "b", "c", "d", "d")
)
# A tibble: 6 × 2
# id value
# <dbl> <chr>
# 1     1     a
# 2     1     a
# 3     2     b
# 4     2     c
# 5     3     d
# 6     3     d

# distinct with Non-Standard Evaluation
df %>% distinct()

# distinct with Standard Evaluation
df %>% distinct_()

# Also, you can set the column names with .dots.
df %>% distinct_(.dots = names(.))
# A tibble: 4 × 2
# id value
# <dbl> <chr>
# 1     1     a
# 2     2     b
# 3     2     c
# 4     3     d

# distinct with data.table
unique(as.data.table(df))
# id value
# 1:  1     a
# 2:  2     b
# 3:  2     c
# 4:  3     d