Analogous function for top_n and top_frac in dplyr, but with a different API.
top_n_dt(data, n, wt = NULL) top_frac_dt(data, n, wt = NULL)
| data | data.frame |
|---|---|
| n | If |
| wt | (Optional). The variable to use for ordering. If not specified, defaults to the last variable in the data.frame. |
data.table
iris %>% top_n_dt(10,Sepal.Length)#> Sepal.Length Sepal.Width Petal.Length Petal.Width Species #> 1: 7.6 3.0 6.6 2.1 virginica #> 2: 7.3 2.9 6.3 1.8 virginica #> 3: 7.2 3.6 6.1 2.5 virginica #> 4: 7.7 3.8 6.7 2.2 virginica #> 5: 7.7 2.6 6.9 2.3 virginica #> 6: 7.7 2.8 6.7 2.0 virginica #> 7: 7.2 3.2 6.0 1.8 virginica #> 8: 7.2 3.0 5.8 1.6 virginica #> 9: 7.4 2.8 6.1 1.9 virginica #> 10: 7.9 3.8 6.4 2.0 virginica #> 11: 7.7 3.0 6.1 2.3 virginicairis %>% top_n_dt(-10,Sepal.Length)#> Sepal.Length Sepal.Width Petal.Length Petal.Width Species #> 1: 4.7 3.2 1.3 0.2 setosa #> 2: 4.6 3.1 1.5 0.2 setosa #> 3: 4.6 3.4 1.4 0.3 setosa #> 4: 4.4 2.9 1.4 0.2 setosa #> 5: 4.3 3.0 1.1 0.1 setosa #> 6: 4.6 3.6 1.0 0.2 setosa #> 7: 4.7 3.2 1.6 0.2 setosa #> 8: 4.4 3.0 1.3 0.2 setosa #> 9: 4.5 2.3 1.3 0.3 setosa #> 10: 4.4 3.2 1.3 0.2 setosa #> 11: 4.6 3.2 1.4 0.2 setosairis %>% top_frac_dt(.1,Sepal.Length)#> Sepal.Length Sepal.Width Petal.Length Petal.Width Species #> 1: 7.0 3.2 4.7 1.4 versicolor #> 2: 6.9 3.1 4.9 1.5 versicolor #> 3: 7.1 3.0 5.9 2.1 virginica #> 4: 7.6 3.0 6.6 2.1 virginica #> 5: 7.3 2.9 6.3 1.8 virginica #> 6: 7.2 3.6 6.1 2.5 virginica #> 7: 7.7 3.8 6.7 2.2 virginica #> 8: 7.7 2.6 6.9 2.3 virginica #> 9: 6.9 3.2 5.7 2.3 virginica #> 10: 7.7 2.8 6.7 2.0 virginica #> 11: 7.2 3.2 6.0 1.8 virginica #> 12: 7.2 3.0 5.8 1.6 virginica #> 13: 7.4 2.8 6.1 1.9 virginica #> 14: 7.9 3.8 6.4 2.0 virginica #> 15: 7.7 3.0 6.1 2.3 virginica #> 16: 6.9 3.1 5.4 2.1 virginica #> 17: 6.9 3.1 5.1 2.3 virginicairis %>% top_frac_dt(-.1,Sepal.Length)#> Sepal.Length Sepal.Width Petal.Length Petal.Width Species #> 1: 4.7 3.2 1.3 0.2 setosa #> 2: 4.6 3.1 1.5 0.2 setosa #> 3: 4.6 3.4 1.4 0.3 setosa #> 4: 4.4 2.9 1.4 0.2 setosa #> 5: 4.8 3.4 1.6 0.2 setosa #> 6: 4.8 3.0 1.4 0.1 setosa #> 7: 4.3 3.0 1.1 0.1 setosa #> 8: 4.6 3.6 1.0 0.2 setosa #> 9: 4.8 3.4 1.9 0.2 setosa #> 10: 4.7 3.2 1.6 0.2 setosa #> 11: 4.8 3.1 1.6 0.2 setosa #> 12: 4.4 3.0 1.3 0.2 setosa #> 13: 4.5 2.3 1.3 0.3 setosa #> 14: 4.4 3.2 1.3 0.2 setosa #> 15: 4.8 3.0 1.4 0.3 setosa #> 16: 4.6 3.2 1.4 0.2 setosa