Select column from data.frame

Analogous function for select in dplyr.

select_dt(data, ..., cols = NULL)

Arguments

data	data.frame
...	List of variables or name-value pairs of summary/modifications functions.
cols	(Optional)A numeric or character vector.

Value

data.table

See also

select

Examples

iris %>% select_dt(Species)
#>        Species
#>   1:    setosa
#>   2:    setosa
#>   3:    setosa
#>   4:    setosa
#>   5:    setosa
#>  ---          
#> 146: virginica
#> 147: virginica
#> 148: virginica
#> 149: virginica
#> 150: virginica
iris %>% select_dt(Sepal.Length,Sepal.Width)
#>      Sepal.Length Sepal.Width
#>   1:          5.1         3.5
#>   2:          4.9         3.0
#>   3:          4.7         3.2
#>   4:          4.6         3.1
#>   5:          5.0         3.6
#>  ---                         
#> 146:          6.7         3.0
#> 147:          6.3         2.5
#> 148:          6.5         3.0
#> 149:          6.2         3.4
#> 150:          5.9         3.0
iris %>% select_dt(c("Sepal.Length","Sepal.Width"))
#>      Sepal.Length Sepal.Width
#>   1:          5.1         3.5
#>   2:          4.9         3.0
#>   3:          4.7         3.2
#>   4:          4.6         3.1
#>   5:          5.0         3.6
#>  ---                         
#> 146:          6.7         3.0
#> 147:          6.3         2.5
#> 148:          6.5         3.0
#> 149:          6.2         3.4
#> 150:          5.9         3.0
iris %>% select_dt(1:3)
#>      Sepal.Length Sepal.Width Petal.Length
#>   1:          5.1         3.5          1.4
#>   2:          4.9         3.0          1.4
#>   3:          4.7         3.2          1.3
#>   4:          4.6         3.1          1.5
#>   5:          5.0         3.6          1.4
#>  ---                                      
#> 146:          6.7         3.0          5.2
#> 147:          6.3         2.5          5.0
#> 148:          6.5         3.0          5.2
#> 149:          6.2         3.4          5.4
#> 150:          5.9         3.0          5.1
iris %>% select_dt(1,3)
#>      Sepal.Length Petal.Length
#>   1:          5.1          1.4
#>   2:          4.9          1.4
#>   3:          4.7          1.3
#>   4:          4.6          1.5
#>   5:          5.0          1.4
#>  ---                          
#> 146:          6.7          5.2
#> 147:          6.3          5.0
#> 148:          6.5          5.2
#> 149:          6.2          5.4
#> 150:          5.9          5.1
iris %>% select_dt("Pe")
#>      Petal.Length Petal.Width
#>   1:          1.4         0.2
#>   2:          1.4         0.2
#>   3:          1.3         0.2
#>   4:          1.5         0.2
#>   5:          1.4         0.2
#>  ---                         
#> 146:          5.2         2.3
#> 147:          5.0         1.9
#> 148:          5.2         2.0
#> 149:          5.4         2.3
#> 150:          5.1         1.8
iris %>% select_dt("Pe|Sp")
#>      Petal.Length Petal.Width   Species
#>   1:          1.4         0.2    setosa
#>   2:          1.4         0.2    setosa
#>   3:          1.3         0.2    setosa
#>   4:          1.5         0.2    setosa
#>   5:          1.4         0.2    setosa
#>  ---                                   
#> 146:          5.2         2.3 virginica
#> 147:          5.0         1.9 virginica
#> 148:          5.2         2.0 virginica
#> 149:          5.4         2.3 virginica
#> 150:          5.1         1.8 virginica
iris %>% select_dt(cols = 2:3)
#>      Sepal.Width Petal.Length
#>   1:         3.5          1.4
#>   2:         3.0          1.4
#>   3:         3.2          1.3
#>   4:         3.1          1.5
#>   5:         3.6          1.4
#>  ---                         
#> 146:         3.0          5.2
#> 147:         2.5          5.0
#> 148:         3.0          5.2
#> 149:         3.4          5.4
#> 150:         3.0          5.1
iris %>% select_dt(cols = names(iris)[2:3])
#>      Sepal.Width Petal.Length
#>   1:         3.5          1.4
#>   2:         3.0          1.4
#>   3:         3.2          1.3
#>   4:         3.1          1.5
#>   5:         3.6          1.4
#>  ---                         
#> 146:         3.0          5.2
#> 147:         2.5          5.0
#> 148:         3.0          5.2
#> 149:         3.4          5.4
#> 150:         3.0          5.1