String slicing

Definition

String slicing is the process of extracting a portion of a string by specifying a start and end index. It allows for accessing substrings in Python efficiently.

5 Must Know Facts For Your Next Test

1. String slicing uses the syntax string[start:end] where 'start' is inclusive and 'end' is exclusive.
2. Negative indices can be used in slicing to count from the end of the string.
3. Omitting the start index defaults to the beginning of the string, while omitting the end index defaults to the end of the string.
4. Slicing with [::step] allows for specifying a step value, which determines how many characters to skip.
5. Strings in Python are immutable, so slicing creates a new string without modifying the original.

Review Questions

• What will be the output of 'hello'[1:4]?
• How do you slice a string to extract every second character?
• Explain what happens when you use negative indices in string slicing.

Related terms

Indexing:

Accessing individual characters in a string using their position within square brackets.

Immutable:

An object whose state cannot be modified after it is created. Strings in Python are immutable.

Substring:

A part or section of a larger string, often obtained through slicing or other methods.