Unload Package without Restarting R (Example)

This tutorial explains how to unload a package without restarting R (or RStudio).

The article is structured as follows:

• Step 1: Install & Load Package in R
• Step 2: Unload Package without Restarting R
• Video & Further Resources

Here’s the step-by-step process:

Step 1: Install & Load Package in R

I’m going to use the stringr package for the example of this R tutorial. Let’s install and load the package to R:

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

The package contains many add-on functions for the manipulation of character strings in the R programming language. For instance, we can use the str_sub function to subset certain characters of a character string:

str_sub(string = "ABCDE", start = 2, end = 4)   # Apply str_sub function
# "BCD"

Works fine. Now let’s assume we don’t need the package anymore and for that reason we want to remove the package from our R session…

Step 2: Unload Package without Restarting R

If we want to unload the stringr package (or any other CRAN package), we can apply the detach command:

detach("package:stringr")                       # Detach stringr package

Note that within the detach function we have to write package: in front of the name of the package (i.e. stringr).

Now, let’s see whether the detaching worked. If we apply the str_sub function again, the following happens:

str_sub(string = "ABCDE", start = 2, end = 4)   # Apply str_sub function

Figure 1: Error Message after Unloading stringr Package.

The function does not exist anymore. We successfully removed the stringr package from our R session!

Video & Further Resources

In case you need further explanations on the removal of packages from an R session, you may have a look at the following video that I have recently published on my YouTube channel. In the video, I’m explaining the example of this tutorial in more detail:

Furthermore, you could have a look at the other R tutorials of this website. Some interesting tutorials can be found below:

• Detach All User-Installed Packages in R
• Find Out Which Package Version is Loaded
• Check if Package is Missing and Install Automatically
• Load Multiple Packages at Once in R
• Introduction to the pacman Package in R
• The attach & detach Functions in R
• R Functions List (+ Examples)
• The R Programming Language

At this point of the article, you should know how to detach a package without closing/shutting down and reopening R (or RStudio). In case you have any further questions, please let me know in the comments section below.