Python Design Patterns 简明教程

Lists Data Structure

Lists 数据结构是 Python 中一个通用的数据类型，它可以写成方括号中逗号分隔的值列表。

The Lists data structure is a versatile datatype in Python, which can be written as a list of comma separated values between square brackets.

Syntax

以下是结构的基本语法 -

Here is the basic syntax for the structure −

List_name = [ elements ];

如果您观察，语法声明为数组，唯一区别在于列表可以包含不同数据类型元素。数组包含相同数据类型的元素。列表可以包含字符串、整数和对象的组合。列表可用于堆栈和队列的实现。

If you observe, the syntax is declared like arrays with the only difference that lists can include elements with different data types. The arrays include elements of the same data type. A list can contain a combination of strings, integers and objects. Lists can be used for the implementation of stacks and queues.

列表是可变的。这些可以根据需要随时更改。

Lists are mutable. These can be changed as and when needed.

How to implement lists?

以下程序显示了列表的实现 -

The following program shows the implementations of lists −

my_list = ['p','r','o','b','e']
# Output: p
print(my_list[0])

# Output: o
print(my_list[2])

# Output: e
print(my_list[4])

# Error! Only integer can be used for indexing
# my_list[4.0]

# Nested List
n_list = ["Happy", [2,0,1,5]]

# Nested indexing

# Output: a
print(n_list[0][1])

# Output: 5
print(n_list[1][3])

Output

上述程序生成以下输出 −

The above program generates the following output −

list data structure

Python 列表的内置函数如下 -

The built-in functions of Python lists are as follows −

  1. Append()− It adds element to the end of list.

  2. Extend()− It adds elements of the list to another list.

  3. Insert()− It inserts an item to the defined index.

  4. Remove()− It deletes the element from the specified list.

  5. Reverse()− It reverses the elements in list.

  6. sort() − It helps to sort elements in chronological order.