Reading contents of a Text File in R Programming - read.table() Function

The read.table() function in R can be used to read a text file's contents. A versatile and often used function for reading tabular data from different file formats, including text files, is read.table(). It returns the data in the form of a table.

Syntax:

read.table(filename, header = FALSE, sep = "")

Parameters:

• header: represents if the file contains header row or not
• sep: represents the delimiter value used in file

Example 1: Reading data from the same directory 

data <- read.table("TextFileExample.txt",
                    header = FALSE, sep = " ")
    
# Printing content of Text File
print(data)

Output:

   V1 V2 V3
1 100  A  a
2 200  B  b
3 300  C  c
4 400  D  d
5 500  E  e
6 600  F  f

Explanation: The file "TextFileExample.txt" is read from the current directory. The header = FALSE argument states that there is no header row in the file, and sep = " " says that columns are separated by spaces.

Example 2: Reading data from a different directory 

# R program to read a text file

# Reading data from another directory
x<-read.table("D://Data//myfile.txt", header = FALSE)
    
# print x
print(x)

Output:

   V1 V2 V3
1 100 a1 b1
2 200 a2 b2
3 300 a3 b3

Reading contents of a Text File in R Programming - read.table() Function - FAQs

Can we specify the column names while reading the text file?

Yes, we can specify column names while reading the text file using the col.names parameter in the read.table() function.

How can we skip header lines or ignore specific rows while reading the text file?

If your text file contains header lines or rows that you want to skip while reading, you can use the skip parameter in the read.table() function. Specify the number
of lines to skip as the value of the skip parameter. For example, to skip the first two lines, you can use.

How to handle missing or incomplete values while reading?

The read.table() function provides the na.strings parameter to handle missing or incomplete values. we can specify the character strings that should be treated as
missing values using this parameter.