R Program to Extract n Characters From a String

We can extract n characters from a given string according to our need.

In R, we can use the str_sub() function of the stringr package to extract n characters from a string.

Example 1: R Program to Extract n Characters From a String

library("stringr") 

string1 <- "codemy"

# extract first three characters
str_sub(string1, 1, 3)  # prints "Pro"

# extract characters from 4th index to 7th index
str_sub(string1, 4, 7)  # prints "gram"

Output

[1] "Pro"
[2] "gram"

In the above example, we have used the str_sub() function of the stringr package to extract n characters from a string.

• str_sub(string1, 1, 3) - prints all characters of string1 from 1st position to 3rd position
• str_sub(string1, 4, 7) - prints all characters of string1 from 4th position to 7th position

Example 2: Extract n Characters From Last in R

library("stringr") 

string1 <- "codemy"

# extract last three characters
str_sub(string1, -3, -1) 

Output: [1] "miz"

In the above example, we have used the negative index to extract characters from the last of a string1.

Here, str_sub(string1, -3, -1) extracts all characters of string1 from 3rd last position -3 to last position -1.