*37*

We can use the following syntax to convert a character vector to a factor vector in R:

factor_vector factor(character_vector)

This tutorial provides several examples of how to use this function in practice.

**Example 1: Convert a Vector from Character to Factor**

The following code shows how to convert a character vector to a factor vector:

#create character vector character_vector #convert character vector to factor vector factor_vector factor(character_vector) #view factor vector factor_vector [1] First Second Third Levels: First Second Third #confirm class of factor vector class(factor_vector) [1] "factor"

**Example 2: Convert a Column from Character to Factor**

The following code shows how to convert a specific column in a data frame from character to factor:

#create data frame df frame(a = c('12', '14', '19', '22', '26'), b = c(28, 34, 35, 36, 40)) #convert column 'a' from character to factor df$a factor(df$a) #view new data frame df a b 1 First 28 2 Second 34 3 Third 40 #confirm class of factor vector class(df$a) [1] "factor"

**Example 3: Convert Several Columns from Character to Factor**

The following code shows how to convert all character columns in a data frame from character to factor:

#create data frame df frame(a = c('12', '14', '19', '22', '26'), b = c('28', '34', '35', '36', '40'), c = as.factor(c(1, 2, 3, 4, 5)), d = c(45, 56, 54, 57, 59)) #display classes of each column sapply(df, class) a b c d "character" "character" "factor" "numeric" #convert all character columns to factor df data.frame(unclass(df), stringsAsFactors = TRUE) #display classes of each column sapply(df, class) a b c d "factor" "factor" "factor" "numeric"

This code made the following changes to the data frame columns:

**Column a:**From character to factor**Column b:**From character to factor**Column c:**Unchanged (since it was already a factor)**Column d:**Unchanged (since it was numeric)

By using the apply() and sapply() functions, we were able to convert only the character columns to factor columns and leave all other columns unchanged.

**Additional Resources**

How to Convert Factor to Character in R

How to Convert Character to Numeric in R

How to Convert Strings to Dates in R