Strings in Python are sequences of characters, and slicing is a powerful technique to extract specific portions. By specifying start and end indices within the string, you can easily manipulate text data.
Basic Slicing
To slice a string, use square brackets [] with the start and end indices separated by a colon :. Indexing begins at 0.
Example:
my_string = "Hello, world!"
print(my_string[0:5]) # Output: Hello
print(my_string[7:]) # Output: world!Omitting Indices
Omitting the Start Index: If you leave out the start index, slicing begins at the beginning of the string.
Omitting the End Index: If you leave out the end index, slicing continues to the end of the string.
Example:
my_string = "Python is awesome!"
print(my_string[:6]) # Output: Python
print(my_string[7:]) # Output: is awesome!Using Negative Indices
Negative indices allow you to count from the end of the string, providing flexible slicing options.
Example:
my_string = "Hello, world!"
print(my_string[-6:]) # Output: world!Step Slicing
For skipping characters, add a step value after the second colon ::. This lets you slice with intervals.
Example:
my_string = "Python is awesome!"
print(my_string[::2]) # Output: Pto i aewsm!Reversing Strings
To reverse a string, use a negative step value of -1.
Example:
my_string = "Hello, world!"
print(my_string[::-1]) # Output: !dlrow ,olleH