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This article mainly introduces "what are the five super-useful functions in Python". In daily operation, I believe that many people have doubts about what the five super-useful functions in Python are. The editor consulted all kinds of materials and sorted out simple and easy-to-use operation methods. I hope it will be helpful for you to answer the doubts about "what are the five super-useful functions in Python?" Next, please follow the editor to study!

1. Introduction

In this article, we use code to illustrate in detail the important role of the five super-practical functions in Python.

These functions are simple, but they are the most powerful functions in Python.

Python has many libraries and built-in functions, and understanding and proper use of these functions can help us program efficiently.

2. Lambda function

Lambda function is one of the most powerful functions in Python, and it is sometimes called anonymous function.

It is called an anonymous function because we can instantiate and declare a function without a name. If you are performing a single operation, it is useful to use the lambda function instead of the traditional function. Lambda is similar to a normal function, except that it can only return one expression.

Next, we use the Lambda function to find the value of the expression (aqb) ^ 2.

The code is as follows:

Answer = lambda a, b: astatine 2 + bauxite 2 + 2*a*bprint (answer (3,6))

The notes are as follows:

The syntax of the Lambda function is: lambda arguments: expression

The Lambda function does not require a function name and returns statements that use the Lambda keyword.

Notice that the above Lambda function is called using the variable answer.

We can also use the Lambda function in other functions.

Lambda is similar to a normal function, except that it can only return one expression.

3. Map function

Map is a Python built-in function that programmers use to simplify the program, which iterates over all specified elements without using any loop.

Next, we use the Map function to sum the two corresponding elements of list and generate a new list

Def add_list (aformab): return a+boutput = list (map (add_list, [2mai 6mai 3], [3dre 4m 5]) print (output)

The notes are as follows:

The syntax of the Map function is: map (function,iterables)

In the above example, the function of our custom function add_list is to sum two variables.

The result of the above example is another list [5, 10, 8]

If we want to explore more of the functions of map functions, we can replace the above functions with lambda, or we can operate not only on list, but also on tuple and set.

4. Filter function

Filter is another built-in function in Python, which is useful when you need to distinguish between other types of data. The Filter function is often used to extract data based on specific filtering criteria.

Def is_positive (a): return a > 0output = list (filter (is_positive, [1mai Lashi 2je 3m Lay 4je 5je 6]) print (output)

The notes are as follows:

The syntax of the Filter function is: filter (function,iterable)

The above custom function must require a value of type Bool to be returned

The Filter function returns only those elements that satisfy the true return value of the custom function.

The return value of the above example is [1, 3, 5, 6].

5. Zip function

Zip is another built-in function in Python that is mainly used to extract data from different columns in the database and combine it into tuples.

User_id = ["12121", "56161", "33287", "23244"] user_name = ["Mick", "John", "Tessa", "Nick"] user_info = list (zip (user_name,user_id)) print (user_info)

The notes are as follows:

The syntax of the Zip function is: zip (* iterables)

The main purpose of this function is to combine two given lists into a tuple.

The output of the above example is [('Mick',' 12121'), ('John',' 56161'), ('Tessa',' 33287'), ('Nick',' 23244')]

6. Reduce function

Use the Reduce function when you need to use the same operation for all elements in a given list.

The code is as follows:

Import functoolsdef sum_two_elements (sum_two_elements, numbers): return a+bnumbers = [6 functools.reduce (sum_two_elements, numbers) print (result)]

The notes are as follows:

The syntax of the Reduce function is: functools.reduce (function, iterable)

The Reduce function is not a Python built-in function. You need to import the functools module when using this function.

The output of the above code is 16, which implements the function of summing all the elements of list.

At this point, the study of "what are the five super useful functions in Python" is over. I hope to be able to solve your doubts. The collocation of theory and practice can better help you learn, go and try it! If you want to continue to learn more related knowledge, please continue to follow the website, the editor will continue to work hard to bring you more practical articles!

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