Extracting substrings is a common operation in Python programming. Python provides several ways to obtain a substring from a string using slicing and built-in functions.
Using String Slicing
The most common method is to use slicing:
string = "Hello, World!"
substring = string[start:end]
Example:
substring = string[7:12]
print(substring) # Output: World
Omitting Start or End Index
You can omit the start or end index to slice from the beginning or to the end:
print(string[:5]) # Output: Hello
print(string[7:]) # Output: World!
Using Negative Indices
Negative indices count from the end of the string:
print(string[-6:-1]) # Output: World
Using split() Method
You can split the string and access parts of it:
parts = string.split(", ")
print(parts[1]) # Output: World!
Conclusion
Python’s slicing syntax and string methods make it easy to extract substrings. Mastering these techniques is essential for effective string manipulation.