Convert all character columns to factors using dplyr in R

character2factor.r

library(dplyr)
iris_char <- iris %>%
  mutate(Species=as.character(Species),
         char_column=sample(letters[1:5], nrow(iris), replace=TRUE))
sum(sapply(iris_char, is.character)) # 2

iris_factor <- iris_char %>%
  mutate_if(sapply(iris_char, is.character), as.factor)
# Sepal.Length  Sepal.Width Petal.Length  Petal.Width      Species  char_column 
# "numeric"    "numeric"    "numeric"    "numeric"  "character"  "character" 

sapply(iris_factor, class)
# Sepal.Length  Sepal.Width Petal.Length  Petal.Width      Species  char_column 
# "numeric"    "numeric"    "numeric"    "numeric"     "factor"     "factor" 

Awesome!

This code colved my problem of column type conversion in a dataframe.
mutate( column_1 = as.character(column_1))

Or you could use:
iris_factor <- iris_char %>% type.convert()

Is sapply necessary here? I think
iris_factor <- iris %>% mutate_if(is.character,as.factor)
works just as well.

Apparently mutate_if (and mutate_all and mutate_at) have been superseded by across:
iris_factor <- iris %>% mutate(across(where(is_character),as_factor))
(although I like mutate_if for this problem).

This helped me a lot! Thank you! 👍

Was struggling a lot with a dataset of 81 variables, was finding a way to convert characters into factors, this is perfect!

Is sapply necessary here? I think
iris_factor <- iris %>% mutate_if(is.character,as.factor)
works just as well.

This works fine!

This worked beautifully, can't believe I didn't have this in my code before! I pull from a oracle database that default assigns every column to either int or chr, and this add-on allows me to do quick QA to make sure all the appropriate rows were pulled and none were dropped. Thank you!

Does this work while using case_when also? Thanks :)