Retrieve column names from a data frame

dta_columns() retrieves the names of specified columns from a data frame or tibble.

Usage

dta_columns(dat, .columns, is_one_column = FALSE)

Arguments

dat

A data frame or tibble from which to select columns.

.columns

Column name(s) to be selected from dat. Supports tidy selection syntax.

is_one_column

A logical value indicating whether only one column should be selected. If TRUE and more than one column is selected, an error is thrown. Default is FALSE.

Value

A character vector containing the names of the selected columns.

Examples

data(mtcars)
dta_gtable(head(mtcars))


  
mpg
      
cyl
      
disp
      
hp
      
drat
      
wt
      
qsec
      
vs
      
am
      
gear
      
carb
    
21.0
6
160
110
3.90
2.620
16.46
0
1
4
4
21.0
6
160
110
3.90
2.875
17.02
0
1
4
4
22.8
4
108
93
3.85
2.320
18.61
1
1
4
1
21.4
6
258
110
3.08
3.215
19.44
1
0
3
1
18.7
8
360
175
3.15
3.440
17.02
0
0
3
2
18.1
6
225
105
2.76
3.460
20.22
1
0
3
1

dta_columns(mtcars, .columns = starts_with("c"))
#> [1] "cyl"  "carb"

dta_columns(mtcars, .columns = cyl:wt)
#> [1] "cyl"  "disp" "hp"   "drat" "wt"  

dta_columns(mtcars, .columns = c(mpg, hp, vs, gear))
#> [1] "mpg"  "hp"   "vs"   "gear"

try(dta_columns(mtcars, .columns = c(mpg, hp, vs, gear), is_one_column = TRUE))
#> Error in dta_columns(mtcars, .columns = c(mpg, hp, vs, gear), is_one_column = TRUE) : 
#>   Expected 1 column but got 4 columns