Getting Substrings in Python
How do you extract a portion of a string in Python? The answer lies in the language's powerful string slicing feature.
String slicing allows you to obtain a substring by specifying the starting and ending indices using square brackets. By default, the first character of the string has an index of 0.
Syntax:
string[start:end]
Options:
- Omitting the start index: Starts from the beginning of the string.
- Omitting the end index: Extracts to the end of the string.
Examples:
>>> x = "Hello World!" >>> x[2:] # From character 3 to the end 'llo World!' >>> x[:2] # From the start to character 2 'He' >>> x[:-2] # From the start to 2 characters before the end 'Hello Worl' >>> x[-2:] # From 2 characters before the end to the end 'd!' >>> x[2:-2] # From character 3 to 2 characters before the end 'llo Worl'
This concept is known as "slicing" in Python and extends beyond strings. Refer to the documentation for a comprehensive explanation.
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