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The len function is a built-in function used to return the length or number of elements of an object (string, list, tuple, etc.). The use of the len function is very simple. You only need to pass the object whose length needs to be obtained as a parameter to the len function. Common usage scenarios are: 1. Calculation of string length. A string is composed of a series of characters. You can use the len function to obtain the length of a string, that is, the number of characters. 2. Calculation of list length. You can use the len function to obtain it. The number of elements in the list; 3. Tuple length calculation, etc.
# Operating system for this tutorial: Windows 10 system, Dell G3 computer.
The len function is a built-in function that returns the length or number of elements of an object (string, list, tuple, etc.). In Python, the len function is very commonly used. It can help us quickly obtain the length of an object, making it convenient for us to perform various operations.
The use of the len function is very simple. We only need to pass the object whose length needs to be obtained as a parameter to the len function. The following are some common usage scenarios and examples:
String length calculation
A string is composed of a series of characters, we can use the len function to get the string The length, that is, the number of characters. For example:
string = "Hello, World!" length = len(string) print(length) # 输出:13
In the above example, the len function returns the length of the string "Hello, World!", which is 13.
List length calculation
List is one of the commonly used data structures in Python. We can use the len function to get the number of elements in the list. For example:
list = [1, 2, 3, 4, 5] length = len(list) print(length) # 输出:5
In the above example, the len function returns the length of the list [1, 2, 3, 4, 5], which is 5.
Tuple length calculation
Tuple is also one of the commonly used data structures in Python. We can also use the len function to get the number of elements in the tuple. For example:
tuple = (1, 2, 3, 4, 5) length = len(tuple) print(length) # 输出:5
In the above example, the len function returns the length of the tuple (1, 2, 3, 4, 5), which is 5.
Dictionary length calculation
Dictionary is one of the commonly used data structures in Python, which consists of key-value pairs. We can also use the len function to get the number of key-value pairs in the dictionary. For example:
dict = {"name": "John", "age": 25, "city": "New York"} length = len(dict) print(length) # 输出:3
In the above example, the len function returns the length of the dictionary {"name": "John", "age": 25, "city": "New York"}, which is 3.
It should be noted that the len function can only be used for iterable objects, that is, those objects that can be traversed using a for loop. For other types of objects, such as integers, floating point numbers, Boolean values, etc., the len function will report an error.
The len function is a very commonly used function, which can help us quickly obtain the length or number of elements of an object. Whether it is a string, list, tuple or dictionary, the len function can be used. Using the len function can make our code more concise and efficient.
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