Resetting R's options() to Default Values
Sometimes, you might find yourself in a situation where you've changed R's global options using options(), but you want to revert them back to their original defaults. Perhaps you made a mistake, or you just want to start fresh with a clean slate. This article will guide you through the process of resetting options() to their default values.
Understanding the Problem
options() in R is a powerful tool for customizing the way R behaves. It allows you to change things like the number of digits displayed, the warning messages shown, and even the directory where R saves its files. However, making changes to options() can sometimes lead to unexpected behavior, especially when working in projects with multiple users or collaborating on code.
The Challenge: Resetting Options
The challenge lies in the fact that there isn't a direct function to simply reset all options() to their defaults. R doesn't store a copy of the original defaults. Therefore, we need to use a workaround to achieve this.
Solution: Leveraging Default Values
The solution involves creating a temporary environment where we can temporarily store the default values of options(). Here's how:
-
Create a temporary environment:
tmp <- new.env() -
Copy the default options:
options(tmp) -
Reset the current options:
options(tmp[[".Options"]])
This sequence of commands first creates a new, empty environment called tmp. Then, we use options(tmp) to copy the current options into the tmp environment. This effectively stores the current state of the options.
Finally, we reset the current options by using options(tmp[[".Options"]]), which reads the options from the .Options variable stored within the temporary environment. This ensures that all options are restored to their default values.
Example:
Let's illustrate this with a simple example. Suppose you change the digits option:
options(digits = 3)
This will now display only three digits for numeric values. To reset this back to the default (usually 7), you can use the following code:
tmp <- new.env()
options(tmp)
options(tmp[[".Options"]])
Additional Notes:
-
Specific options: If you want to reset only specific options, you can directly assign their default values. For instance, to reset the
digitsoption, useoptions(digits = 7). -
Caution: Resetting
options()to default values can sometimes lead to undesired side effects. If you're unsure about the consequences, it's best to consult the R documentation or seek advice from experienced R users. -
RStudio shortcut: In RStudio, you can reset most options by using the "Restore Default Settings" button in the "Tools" menu.
By understanding how to reset options(), you can ensure that R's settings remain consistent and avoid potential complications in your workflow.
