How to Run an R Script in R: Simple Steps

To run an R script in R, use the source() function with the script file path as the argument, like source('script.R'). This executes all the commands inside the script in your current R session.

Syntax

The basic syntax to run an R script is using the source() function.

• source('path/to/script.R'): Runs the script located at the given path.
• The path can be relative or absolute.
• All commands in the script run as if typed in the console.

r

source('script.R')

Example

This example shows how to run a simple R script that prints a message and calculates a sum.

r

# Contents of example_script.R
print('Hello from script!')
result <- 5 + 3
print(paste('Sum is', result))

# Run the script in R
source('example_script.R')

Output

[1] "Hello from script!"
[1] "Sum is 8"

Common Pitfalls

Common mistakes when running R scripts include:

• Using wrong file path or forgetting the file extension .R.
• Running source() without setting the working directory correctly.
• Expecting output if the script does not print or return anything.

Always check your current working directory with getwd() and set it with setwd() if needed.

r

# Wrong way: missing file extension
source('example_script')

# Right way: include extension
source('example_script.R')

Quick Reference

Command	Description
source('file.R')	Run all commands in the R script file
getwd()	Show current working directory
setwd('path')	Change working directory to specified path
print()	Display output in console
file.exists('file.R')	Check if script file exists

Key Takeaways

Use source('script.R') to run an R script inside R.

Ensure the script file path is correct and includes the .R extension.

Check and set your working directory to find the script file.

Scripts run as if commands are typed directly in the console.

Use print() in scripts to see output when running source().