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This article mainly introduces "what are the advanced Python functions". In daily operation, I believe many people have doubts about what problems there are in the advanced Python functions. Xiaobian consulted all kinds of information and sorted out simple and easy operation methods. I hope to help you answer the doubts about "what are the advanced Python functions"! Next, please follow the small series to learn together!

1. map()

map() is a built-in Python function that applies a function to a sequence of elements, such as a list or dictionary. It is probably the easiest and most readable way to manipulate data.

The following example is intended to find the square of a number in a list. First of all, it is necessary to specify the functions used. Next, the author shows and compares methods that use map() and methods that do not use map(), that is, python and non-python methods.

nums = [1, 2, 3, 4, 5]# this function will calculate square def square_num(x): return x**2 # non-pythonic approach squares = [] for num in nums: squares.append(square_num(num)) print('Non-Pythonic Approach: ', squares) # pythonic approach x = map(square_num, nums) print('Pythonic Approach: ', list(x))

The output is essentially the same, but the python method is significantly simpler and the process does not require loops.

2. zip ()

zip() is one of my favorite functions. It allows users to iterate over two or more lists simultaneously. This feature is useful for both date and time problems.

For example, if it is used daily at work, the user has the first attribute to indicate the start time of the event and the second attribute to indicate the end time of the event. Think further, there is always a need to calculate the time difference between events at work, and zip is by far the easiest way to do it.

The example creates two lists of numbers with the task of summing the corresponding elements:

first = [1, 3, 8, 4, 9] second = [2, 2, 7, 5, 8] # Iterate over two or more list at the same time for x, y in zip(first, second): print(x + y)

This is simple and clean.

3. filter()

The filter() function is somewhat similar to the map() function--it also applies a function to a sequence, except that filter() returns only elements with True values.

In the example below, the author creates a list of arbitrary numbers and a function that returns True if the number is even. Again, the author will demonstrate how to perform this operation in both non-python and python ways.

numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] # Will return true if input number is even def even(x): return x % 2 == 0 # non-pythonic approach even_nums = [] for num in numbers: if even(num): even_nums.append(num) print('Non-Pythonic Approach: ', even_nums) # Pythonic approach even_n = filter(even, numbers) print ('Pythonic Approach:', list(even_n)) At this point, the study of "what are the advanced Python functions" is over, hoping to solve everyone's doubts. Theory and practice can better match to help everyone learn, go and try it! If you want to continue learning more relevant knowledge, please continue to pay attention to the website, Xiaobian will continue to strive to bring more practical articles for everyone!

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