Python3 list

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

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

Sequence of operations can be carried out, including indexing, slicing, add, multiply, check the members.

Moreover, Python has a built-determine the length of the sequence and determining the maximum and minimum element method.

Python is a list of the most commonly used type of data, it can be used as a comma-separated values ​​appear in square brackets.

List of data items need not have the same type

Create a list as long as the comma-delimited data items using different brackets can be. As follows:

list1 = ['Google', 'w3big', 1997, 2000];
list2 = [1, 2, 3, 4, 5 ];
list3 = ["a", "b", "c", "d"];

With the index of the string as a list of index starts from 0. List can be intercepted, combinations and the like.

Access list value

Use subscripting to access values ​​in the list, you can also use square brackets in the form of interception of character, as follows:

#!/usr/bin/python3

list1 = ['Google', 'w3big', 1997, 2000];
list2 = [1, 2, 3, 4, 5, 6, 7 ];

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

Running instance >> Download

Examples of the above output:

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

update list

#!/usr/bin/python3

list = ['Google', 'w3big', 1997, 2000]

print ("第三个元素为 : ", list[2])
list[2] = 2001
print ("更新后的第三个元素为 : ", list[2])

We will discuss the use of the next chapter in the append () method: Note

Examples of the above output:

第三个元素为 :  1997
更新后的第三个元素为 :  2001

Remove list element

You can use the del statement to remove elements of the list, the following examples:

#!/usr/bin/python3

list = ['Google', 'w3big', 1997, 2000]

print (list)
del list[2]
print ("删除第三个元素 : ", list)

Examples of the above output:

删除第三个元素 :  ['Google', 'w3big', 2000]

We will discuss the use of the next chapter in the remove () method: Note

Python script list operator

List of + and * operators and string similarity. + Sign for the combined list, an asterisk for the repeat list.

As follows:

Python list interception and splicing

Python list interception string type of operation, as follows:

L=['Google', 'w3big', 'Taobao']

operating:

>>> L=['Google', 'w3big', 'Taobao']
>>> L[2]
'Taobao'
>>> L[-2]
'w3big'
>>> L[1:]
['w3big', 'Taobao']
>>> 

The list also supports the splicing operation:

>>> squares = [1, 4, 9, 16, 25]
>>> squares + [36, 49, 64, 81, 100]
[1, 4, 9, 16, 25, 36, 49, 64, 81, 100]

Nested list

Nested list is created using the other lists in the list, for example:

>>> a = ['a', 'b', 'c']
>>> n = [1, 2, 3]
>>> x = [a, n]
>>> x
[['a', 'b', 'c'], [1, 2, 3]]
>>> x[0]
['a', 'b', 'c']
>>> x[0][1]
'b'

Python list of functions & methods

Python includes the following functions:

Python includes the following methods: