Python Basics 5-List

List common actions

Slices: Fetching multiple elements

>>> names = [' Amy ', ' Bob ', ' Cindy ', ' David ']>>> names[1:4][' Bob ', ' Cindy ', ' David ']>>> names[ -1] ' David ' >>> names[:-1][' Amy ', ' Bob ', ' Cindy ']>>> names[::2][' Amy ', ' Cindy ']>>> names[:3 [' Amy ', ' Bob ', ' Cindy ']>>> names[1:][' Bob ', ' Cindy ', ' David ']

Additional

>>> names = [' Amy ', ' Bob ', ' Cindy ', ' David ']>>> names. Append (' Eric ') >>> names[' Amy ', ' Bob ', ' Cindy ', ' David ', ' Eric '

Insert

>>> names[' Amy ', ' Bob ', ' Cindy ', ' David ', ' Eric ']>>> names. Insert (2, ' Insert from behind Bob ') >>> names[' Amy ', ' Bob ', ' Insert from behind Bob ', ' Cindy ', ' David ', ' Eric ']

Modify

>>> names[' Amy ', ' Bob ', ' Insert from behind Bob ', ' Cindy ', ' David ', ' Eric ']>>> names[2] = ' Baby ' >>> names[' Amy ', ' Bob ', ' Baby ', ' Cindy ', ' David ', ' Eric '

Delete

>>> names[' Amy ', ' Bob ', ' Baby ', ' Cindy ', ' David ', ' Eric ']>>> del names[2]>>> names[' Amy ', ' Bob ', ' Cindy ', ' David ', ' Eric ']>>> names. Remove (' David ') >>> names[' Amy ', ' Bob ', ' Cindy ', ' Eric ']>>> names. Pop () ' Eric ' >>> names[' Amy ', ' Bob ', ' Cindy '

Extended

>>> names[' Amy ', ' Bob ', ' Cindy ']>>> age = [18,28,38]>>> names. Extend (age) >>> names[' Amy ', ' Bob ', ' Cindy ', 18, 28, 38]

Copy

>>> names[' Amy ', ' Bob ', ' Cindy ', 38]>>> names_copy = names. Copy () >>> names_copy[' Amy ', ' Bob ', ' Cindy ', +, 38]>>> names.remove ($) >>> names[' Amy ', ' Bob ', ' Cindy ', 28]>>> names_copy[' Amy ', ' Bob ', ' Cindy ', 18, 28, 38]

Statistics

>>> names.append >>> names[' Amy ', ' Bob ', ' Cindy ',,, and 28]>>> names. Count (28) 2

Sort & Flip

>>> Names.sort () Traceback (most recent):  File "<stdin>", line 1, in <module>typeerror : Unorderable types:int () < Str ()  #Python3.0 Different data types cannot be sorted together >>> names[3] = ' + ' >>> names[4] = ' 28 ' >>> ' Amy ', ' Bob ', ' Cindy ', ' names[', ']>>> ' names. Sort () >>> names[' + ', ' I ', ' Amy ', ' Bob ', ' Cindy ']>>> names[', ' I ', ' Amy ', ' Bob ', ' Cindy ']>>> Names. Reverse () >>> names[' Cindy ', ' Bob ', ' Amy ', ' 28 ', ' 18 '

Get subscript

>>> names[' Cindy ', ' Bob ', ' Amy ', ' ['] ', ' ' + ', ']>>> ' names. Index (' 3 ')      #只返回找到的第一下标

　　

List-related functions

Serial Number	function
1	Len (list) Number of list elements
2	Max (list) Returns the maximum value of a list element
3	MIN (list) Returns the minimum value of a list element
4	List (seq) Convert a tuple to a list

　　

List of built-in methods

Serial Number	Method
1	List.append (obj) Add a new object at the end of the list
2	List.count (obj) Count the number of occurrences of an element in a list
3	List.extend (seq) Append multiple values from another sequence at the end of the list (extend the original list with a new list)
4	List.index (obj) Find the index position of the first occurrence of a value from the list
5	List.insert (index, obj) Inserting an object into a list
6	List.pop (Obj=list[-1]) Removes an element from the list (the last element by default), and returns the value of the element
7	List.remove (obj) To remove the first occurrence of a value in a list
8	List.reverse () Reverse List of elements
9	List.sort ([func]) Sort the original list
10	List.clear () Clear List
11	List.copy () Copy List

　　

　　

　　

　

Python Basics 5-List