Remove All Special Characters from String in R (2 Examples)

In this R programming tutorial you’ll learn how to delete punctuation and non-alphanumeric characters from a character string.

The article will consist of two examples for the removal of special characters. To be more precise, the content of the page looks as follows:

It’s time to dive into the examples!

Example Data & Packages

The following data is used as basement for this R programming language tutorial:

my_string <- "aaa!$%bbbêéè)(/&ßßß"                # Example string
my_string                                         # Print example string
# "aaa!$%bbbêéè)(/&"

As you can see based on the previous output of the RStudio console, the example data is a character string containing many special characters.

For the examples of this tutorial, we’ll also need to install and load the stringr package:

install.packages("stringr")                       # Install stringr package
library("stringr")                                # Load stringr

The stringr package includes the str_replace_all function, which we will use in the examples of this tutorial.

Example 1: Remove All Non-Alphanumeric Characters

In this Example, I’ll show how to extract all non-alphanumeric characters from our character string.

str_replace_all(my_string, "[^[:alnum:]]", "")    # Delete non-alphanumeric
# "aaabbbêéè"

Example 2: Remove All Punctuation Characters

The following R programming code explains how to clean punctuation (also called interpunction) from our string.

str_replace_all(my_string, "[[:punct:]]", "")     # Delete punctuation
# "aaa$bbbêéè"

In contrast to Example 1, the $-sign is kept.

Video & Further Resources

Do you need further information on the R syntax of this tutorial? Then you might want to have a look at the following video of my YouTube channel. I’m explaining the R programming codes of the present tutorial in the video.

The YouTube video will be added soon.

Also, you could read the related tutorials of my website:

• Replace Specific Characters in String
• str_replace & str_replace_all Functions in R
• Introduction to the stringr Package
• The R Programming Language

To summarize: In this post you learned how to strip special characters in R programming. In this tutorial, I have shown how to remove characters in a single data object. However, we could apply the same syntax to a vector variable or an entire data frame column. In case you have additional comments and/or questions, let me know in the comments section below.