What does list mean in python

Sequence is the most basic data structure in Python. Each element in the sequence is assigned a number - its position, or index, with the first index being 0, the second index being 1, and so on.

Python has 6 built-in types for sequences, but the most common are lists and tuples.

Operations that can be performed on sequences include indexing, slicing, adding, multiplying, and checking members.

In addition, Python has built-in methods for determining the length of a sequence and determining the largest and smallest elements.

List is the most commonly used Python data type, which can appear as a comma-separated value within square brackets.

The data items of the list do not need to be of the same type

To create a list, just use square brackets to enclose the different data items separated by commas. It looks like this:

list1 = ['physics', 'chemistry', 1997, 2000]
list2 = [1, 2, 3, 4, 5 ]
list3 = ["a", "b", "c", "d"]

Like string indexing, list indexing starts at 0. Lists can be intercepted, combined, etc.

Access the values ​​in the list:

Use the subscript index to access the values ​​in the list. You can also use square brackets to intercept characters, as shown below:

#!/usr/bin/python

list1 = ['physics', 'chemistry', 1997, 2000]
list2 = [1, 2, 3, 4, 5, 6, 7 ]

print "list1[0]: ", list1[0]
print "list2[1:5]: ", list2[1:5]

The above example output results:

list1[0]:  physics
list2[1:5]:  [2, 3, 4, 5]

Update list

You can modify or update the data items in the list, or you can use the append() method to add List items, as shown below:

#!/usr/bin/python
# -*- coding: UTF-8 -*-

list = []          ## 空列表
list.append('Google')   ## 使用 append() 添加元素
list.append('Runoob')
print list

Output results of the above example:

['Google', 'Runoob']

Delete list elements

You can use the del statement to delete elements of the list, as shown in the following example :

#!/usr/bin/python
list1 = ['physics', 'chemistry', 1997, 2000]
print list1
del list1[2]
print "After deleting value at index 2 : "
print list1

Output results of the above examples:

['physics', 'chemistry', 1997, 2000]
After deleting value at index 2 :
['physics', 'chemistry', 2000]

For more Python-related technical articles, please visit the Python Tutorial column to learn!

The above is the detailed content of What does list mean in python. For more information, please follow other related articles on the PHP Chinese website!