Using the select-like mechanism to select variables for a single call in dplyr

Desired Results

Using simple syntax, I filter the columns vsand amleaving the values ​​as well cyl.

data(mtcars)
dta <- mtcars[,c("vs", "am", "cyl")]
# Desired results
dta %>% distinct(vs, am, .keep_all = TRUE)

Desired Syntax

I would like to reverse the syntax above and select different cases for all values, excluding the column cylcorresponding to the example below:

dta %>% distinct(vars(-contains("cyl")), .keep_all = TRUE)

which naturally does not work:

>> dta %>% distinct(vars(-contains("cyl")), .keep_all = TRUE)
   vs am cyl vars(-contains("cyl"))
1   0  1   6      ~-contains("cyl")
2   0  1   6      ~-contains("cyl")
3   1  1   4      ~-contains("cyl")
4   1  0   6      ~-contains("cyl")
5   0  0   8      ~-contains("cyl")
6   1  0   6      ~-contains("cyl")
7   0  0   8      ~-contains("cyl")
+4
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1 answer

If you are not opposed to using distinct, you can use group_by_attogether with sliceto get the desired result, i.e.

library(dplyr)

dta %>% 
 group_by_at(vars(-cyl)) %>% 
 slice(1L)

# A tibble: 4 x 3
# Groups:   vs, am [4]
#     vs    am   cyl
#  <dbl> <dbl> <dbl>
#1     0     0     8
#2     0     1     6
#3     1     0     6
#4     1     1     4
+2
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Source: https://habr.com/ru/post/1681884/


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