How to Convert Character to Factor in R?

The as.factor() method in R Programming Language is used to convert the character vector to factor class.

Converting Character Vector To Factor

Syntax:

as.factor(char-vec)

where char-vec is the character vector

The class indicative of the data type of the vector can be obtained using the class() method. Upon conversion, the data type is returned as a factor. 

class(fac-vec)

where char-vec is the character vector

Example:

R

# declaring a character vector
str_vec < - c("Geeks", "For", "Geeks", "Programming", "Coding")
print("Original String")
print(str_vec)

# getting the class of vector
class(str_vec)

str_mod < - as.factor(str_vec)
print("Modified String")
print(str_mod)

# getting the class of vector
class(str_mod)

Output

[1] "Original String"
[1] "Geeks"       "For"         "Geeks"       "Programming" "Coding"    
[1] "character"
[1] "Modified String"
[1] Geeks       For         Geeks       Programming Coding    
Levels: Coding For Geeks Programming
[1] "factor"

Converting DataFrame Column To Factor Column

Similarly, a dataframe column can be converted to factor type, by referring to the particular data column using df$col-name command in R. 

Example:

R

# declaring a character vector
data_frame < - data.frame(col1=c(1: 5),
                          col2=c("Geeks", "For", "Geeks",
                                 "Programming", "Coding")
                          )
print("Original Class")

# getting the class of vector
class(data_frame$col2)

# modifying the col2 of data frame
data_frame$col2 < - as.factor(data_frame$col2)

print("Modified Class")
class(data_frame$col2)

Output

[1] "Original Class" 
[1] "character" 
[1] "Modified Class" 
[1] "factor"