Get Function Name as Character String in R (2 Examples)

For several reasons, one might be interested in learning how to convert functions to character strings . In this tutorial, I will show two common ways to implement it in the R programming language.

The included topics in this tutorial are as follows:

Let’s get started!

Example 1: Get the Function Name as a Character String via as.character() & substitute()

One way of changing the function name to a character string is to use the as.character() and substitute() functions together. For the demonstration, the method is applied to the all() function of the base() package of R.

allf_ex1 <- as.character(substitute(all))

The success of the transformation can be checked via the typeof() function as shown below.

typeof(allf_ex1)                                               
 
# [1] "character"

Please check now how the function name can be used as a string input in the paste() function.

report1 <- paste(allf_ex1,                       
               sep="",
               "() is one of the functions of the base package.")  
report1    
 
# [1] "all() is one of the functions of the base package."

The same code line wouldn’t work before this transformation. See below.

report <- paste(all,
              sep="",
              "() is one of the functions of the base package.") 
report 
 
# Error in paste(all, sep = "", "() is one of the functions of the base package.") :
# cannot coerce type 'builtin' to vector of type 'character'

Example 2: Get the Function Name as a Character String via deparse() & substitute()

Another way of converting the function name into a string is to use the deparse() and substitute() functions together. The method is applied to the all() function for illustrative purposes like in the previous case.

allf_ex2 <- deparse(substitute(all))                                              
typeof(allf_ex2)
 
# [1] "character"

Please see how this conversion is put to use below.

report2 <- paste(allf_ex2,
               sep="",
               "() is one of the functions of the base package.")
report2                                                                      
 
# [1] "all() is one of the functions of the base package."

Video & Further Resources

We have recently published a video on our YouTube channel, which explains the R syntax of this tutorial. Please find the video instruction below:

The YouTube video will be added soon.

Besides that, you might read the related articles on our website. You can find a selection of other tutorials on related topics such as character strings, data objects, text elements, and variables below.

• Convert Name of Data Object to Character String
• Import Text File as Single Character String
• Convert Character String to Variable Name in R
• Get Frequency of Words in Character String
• All R Programming Examples

You have learned in this article how to transform functions to strings in the R programming language. In case you have additional questions, let me know in the comments.

This page was created in collaboration with Cansu Kebabci. Have a look at Cansu’s author page to get more information about her professional background, a list of all his tutorials, as well as an overview on her other tasks on Statistics Globe.