Python Basics list common operations and knowledge points summary

Listing (list)

The list is the most frequently used data type in Python. A list can accomplish the data structure implementation of most collection classes. It supports characters, numbers, and even strings that can contain lists (so-called nesting). The list is identified by [], which is the most common type of composite data for Python.

Common operations

l=[1,2,3, ' Xyn ', 5]

Code	Meaning	Output
L.append (' a ')	Append an element to the L list	[Xyn, ' 5,1 ', ' a ']
L.insert (0, ' a ')	Insert ' A ' in the position of l[0]	[' A ', ' Xyn ', 5,1]
L.pop (0)	Delete the l[0] position of the element, and output L[0]	[2,3, ' Xyn ', 5,1]
L.remove (1)	Remove the first occurrence of this element in L	[2,3, ' Xyn ', 5,1]
L.count (1)	The number of occurrences of this element 1 in the list	2
L.index (5)	The position of the element 5, without throwing an exception	4
L.extend (list)	Append list, merge elements of list to L	[Xyn, ' 5,1 ', ' A ', ' B ', ' C ']
A=[5,4,8,10,0,88] A.sort () Print a	Sort	[0, 4, 5, 8, 10, 88]
L.reverse ()	Reverse	[88, 0, 10, 8, 4, 5]

String cutting and List compositing

' Tuotatianwang,taibaijinxing,juanliandajiang ' # string manager with ', ' cut, and exist manager_list list of Manager_list=manager.split (', ')# Output cut complete list  manager_list# Use the Join function to turn manager_list into a string again and use spaces to connect elements together new_manager='. Join (Manager_ List)New_manager

Output result: [' Tuotatianwang ', ' taibaijinxing ', ' Juanliandajiang ']
Tuotatianwang taibaijinxing Juanliandajiang

The list is similar to a string, and here is the list quiz, where three items are wrong:

A. For list = [' A ', ' B ', ' C ', ' d ', list[-2:] and list[2:] should have the same result valueB. For list = [' A ', ' B ', ' C ', ' d '], after List.insert (3, ' X '), the value of list is [' A ', ' B ', ' C ', ' X ' , ' d ']C. For list = [' A ', ' B ', ' C ', ' d '], print List.pop (3) will get the output result D d. For list = [' A ', ' B ', ' C ', ' D '], print list[2:] will get output [' B ', ' C ', ' d '] e. The string ' A B C ' is cut by a space and the output can be written as print ' a B C '. Split () F. For list = [' A ', ' B ', ' C ', ' d '], print List.pop (3) will get output [' A ', ' B ', ' C '] g. Synthesis of list = [' A ', ' B ', ' C '] into string ' a|b|c ' and output can be written as print list.join (' | ')




********************************************************************************************************** *********************************************, I'm a split line, don't peek ********************************************* .*********************************************************************************************************** **


d [' C ', ' d ']

F D

G-Correct expression

list = [' A ''B ''c'd']new_list=' | '. Join (list)new_list

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Python Basics list common operations and knowledge points summary