R Program to Replace Substring in a String

1. Introduction

Replacing a substring within a string is a common operation in string manipulation. In R, the function gsub() can be employed to replace all occurrences of a pattern (substring) with a replacement string. In this tutorial, we will explore how to utilize the gsub() function to replace substrings in a string.

2. Program Overview

The program will:

1. Define a string.

2. Specify the substring to be replaced and its replacement.

3. Use the gsub() function to replace the substring.

4. Display the modified string.

3. Code Program

# Define the original string
original_string <- "I love blue skies and blue oceans."

# Specify the substring to be replaced and its replacement
substring_to_replace <- "blue"
replacement_string <- "clear"

# Replace the substring using the gsub() function
modified_string <- gsub(substring_to_replace, replacement_string, original_string)

# Display the modified string
print(modified_string)

Output:

[1] "I love clear skies and clear oceans."

4. Step By Step Explanation

1. We start by defining an "original_string" that contains the text "I love blue skies and blue oceans.".

2. Next, we define the "substring_to_replace", which in this case is "blue", and its "replacement_string", which is "clear".

3. The gsub() function is employed to replace all occurrences of the specified substring in the original string. The first argument to gsub() is the substring to search for, the second argument is the replacement string, and the third argument is the string in which the replacements are to be made.

4. The modified string, after replacements, is stored in the "modified_string" variable.

5. Finally, the print() function is used to display the result, which is "I love clear skies and clear oceans.".

The gsub() function is a versatile tool in R for string manipulation. Apart from replacing substrings, it can also work with regular expressions for more complex pattern matching and replacements.