slice() function is used to create a slice object that specifies how to extract a portion of a sequence such as a string, list or tuple. It allows selecting elements using start, stop and step values. The slice object can then be used with indexing syntax to retrieve the required part of the sequence.
Example: In this example, slice() is used to extract a portion of a string.
s = "Hello World"
res = slice(6, 11)
print(s[res])
Output
World
Explanation: slice(6, 11) extracts characters from index 6 to 10 from the string s.
Syntax
slice(start, stop, step)
Parameters:
- start: Starting index of slicing.
- stop: Ending index of slicing (excluded).
- step (optional): Interval between indexes.
Return Value: Returns a slice object.
Examples
Example 1: In this example, a string is sliced using different slice() objects to extract selected characters.
s = "GeeksforGeeks"
a = slice(5)
b = slice(1, 8, 2)
print(s[a])
print(s[b])
Output
Geeks ekfr
Explanation: slice(5) extracts characters from index 0 to 4, while slice(1, 8, 2) selects every second character from index 1 to 7.
Example 2: In this example, slice() is used to extract elements from a list.
l = [10, 20, 30, 40, 50]
res = slice(1, 4)
print(l[res])
Output
[20, 30, 40]
Explanation: slice(1, 4) extracts list elements from index 1 to 3.
Example 3: In this example, negative indexes are used with slice() to access elements from the end of a tuple.
t = (1, 2, 3, 4, 5)
res = slice(-1, -5, -1)
print(t[res])
Output
(5, 4, 3, 2)
Explanation: slice(-1, -5, -1) starts from the last element and moves backward with a step of -1.