Changing column types with dplyr

Question

I need some help tidying my data. I\'m trying to convert some integers to factors (but not all integers to factors). I think I can do with selecting the variables in question

Answer 1

You can use mutate_at instead. Here's an example using the iris dataframe:

library(dplyr)

iris_factor <- iris %>%
  mutate_at(vars(Sepal.Width, 
                 Sepal.Length), 
            funs(factor))

---

Edit 08/2020

As of dplyr 0.8.0, funs() is deprecated. Use list() instead, as in

library(dplyr)

iris_factor <- iris %>%
  mutate_at(vars(Sepal.Width, 
                 Sepal.Length), 
            list(factor))

And the proof:

> str(iris_factor)
'data.frame':   150 obs. of  5 variables:
 $ Sepal.Length: Factor w/ 35 levels "4.3","4.4","4.5",..: 9 7 5 4 8 12 4 8 2 7 ...
 $ Sepal.Width : Factor w/ 23 levels "2","2.2","2.3",..: 15 10 12 11 16 19 14 14 9 11 ...
 $ Petal.Length: num  1.4 1.4 1.3 1.5 1.4 1.7 1.4 1.5 1.4 1.5 ...
 $ Petal.Width : num  0.2 0.2 0.2 0.2 0.2 0.4 0.3 0.2 0.2 0.1 ...
 $ Species     : Factor w/ 3 levels "setosa","versicolor",..: 1 1 1 1 1 1 1 1 1 1 ...