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HomeBackend DevelopmentPython TutorialHow to Efficiently Extract the N-th Element from a List of Tuples in Python?

How to Efficiently Extract the N-th Element from a List of Tuples in Python?

Extracting N-th Elements from a Tuple List

One might encounter a scenario where one needs to extract specific elements from a list of tuples. Consider the following list:

elements = [(1,1,1),(2,3,7),(3,5,10)]

Suppose you want to extract only the second elements of each tuple. Traditionally, a for loop can be used:

seconds = []
for element in elements:
    seconds.append(element[1])

However, for large lists, this can be inefficient. A more elegant and efficient solution involves utilizing list comprehension:

n = 1 # Nth element
seconds = [x[n] for x in elements]

The n variable specifies which element to extract. In this case, n=1 would extract the second element of each tuple.

Result:

seconds = [1, 3, 5]

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