Conditional update of columns in data.table

Integrate mutate and case_when in dplyr and make a new tidy verb for data.table.

mutate_when(data, ...)

Arguments

data	data.frame
...	the first argument (contents before the first comma) should be the condition, other should be equation(s) just like `mutate_dt`.

Value

data.table

See also

case_when

Examples

iris[3:8,]
#>   Sepal.Length Sepal.Width Petal.Length Petal.Width Species
#> 3          4.7         3.2          1.3         0.2  setosa
#> 4          4.6         3.1          1.5         0.2  setosa
#> 5          5.0         3.6          1.4         0.2  setosa
#> 6          5.4         3.9          1.7         0.4  setosa
#> 7          4.6         3.4          1.4         0.3  setosa
#> 8          5.0         3.4          1.5         0.2  setosa
iris[3:8,] %>%
  mutate_when(Petal.Width == .2,
              one = 1,Sepal.Length=2)
#>    Sepal.Length Sepal.Width Petal.Length Petal.Width Species one
#> 1:          2.0         3.2          1.3         0.2  setosa   1
#> 2:          2.0         3.1          1.5         0.2  setosa   1
#> 3:          2.0         3.6          1.4         0.2  setosa   1
#> 4:          5.4         3.9          1.7         0.4  setosa  NA
#> 5:          4.6         3.4          1.4         0.3  setosa  NA
#> 6:          2.0         3.4          1.5         0.2  setosa   1