How to Use list.files() Function in R

The list.files() function in R used to list out every file in specific folder.

The following methods show how you can do it with syntax.

Method 1: List All Files Using list.files() Function

list.files(path_of_folder)

Method 2: List Files With Specific Extension

list.files(file_path,pattern="csv")

Method 3: List First N Files in Folder

list.files(file_path)[1:n]

The following examples show how to use list.files() function in R.

List All Files in Folder

If I want to list all the files in the CSV_data folder, we can achieve this using the list.files() function:

# Get list of all files in folder 
l <- list.files("CSV_data")

# Print list of files
print(l)

Output:

[1] "Machine_data.csv" "product.csv"      "sample.tsv"       "sample1.csv"

The output shows list of all files in CSV_data folder.

To get count of all files in specific folder you can use length() function:

# Get number of all files in folder 
l <- length(list.files("CSV_data"))

# Print count of files
print(l)

Output:

[1] 4

As the output shows count of all files in CSV_data folder.

Let’s list all CSV files in CSV_data folder using pattern argument:

# Get CSV files from folder 
l <- list.files("CSV_data",pattern = "csv")

# Print list of files
print(l)

Output:

[1] "Machine_data.csv" "product.csv"      "sample1.csv"

Her the output shows list of all CSV files in CSV_data folder.

Let’s see example to get first 3 files from CSV_data folder:

# Get first N files from folder 
l <- list.files("CSV_data")[1:3]

# Print list of files
print(l)

Output:

[1] "Machine_data.csv" "product.csv"      "sample.tsv"

The output shows list of first 3 files from CSV_data folder.

By using this syntax you can get list of files from specific folder that you want.