Day 15: Python Slicing
Understanding Slice Notation in Python
Slice notation in Python is a way to extract a subsequence from a sequence, such as a list, tuple, or string. It is written as start:stop:step, where start is the index of the first item to include, stop is the index of the first item to exclude, and step is the number of items to skip between items.
Extracting Subsequences in Python
numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
# Extract the second to fifth items
# (indexes 1 to 4)
sub_sequence = numbers[1:5]
print(sub_sequence)
# Output: [2, 3, 4, 5]
In the above example, we use slice notation to extract a subsequence from the numbers list.
Skipping Items with Slice Notation in Python
# Extract every second item,
# starting from the second item (index 1)
sub_sequence = numbers[1::2]
print(sub_sequence)
# Output: [2, 4, 6, 8, 10]
In this example, we use slice notation to extract every second item from the numbers list.
Extracting the Last Items with Slice Notation in Python
In this example, we use slice notation to extract the last three items from the numbers list.
By understanding how to use slice notation in Python, you can effectively extract subsequences from your sequences. Stay tuned for more Python-related content.
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