Python 3 list operations

Create List subject = ["Liunx", "Python", "web", "Java"]

#读取列表print (subject) #打印显示 [' Liunx ', ' python ', ' web ', ' Java '] #列表的切片, the slice index is the 0-based print (subject[0]) # NO. 0 index, That is, the first element of the list print (subject[1]) print (subject[2]) print (subject[3]) print (Subject[1:3]) # reads the second element of the list to the fourth element, the fourth element is not taken, Halves print (subject[-1]) #读取列表的最后一个元素print (Subject[-2]) # reads the penultimate element of the list print (subject[-3:]) #读取列表的倒数第三个元素至最后一个元素 # Print show liunxpythonwebjava[' python ', ' web ']javaweb[' python ', ' web ', ' Java '

Append to List

Create List subject = ["Liunx", "Python", "web", "Java"]

#追加列表subject. Append ("PHP") #打印列表print (subject) [' Liunx ', ' python ', ' web ', ' Java ', ' php ']# #追加内容到指定的位置subject. Insert (1 , "Windows") # inserts Windows into the # 1th index # Print List (subject) [' Liunx ', ' windows ', ' Python ', ' web ', ' Java ', ' php '] # 1th index has become windows Subject.insert (2, "UI") #打印 list print (subject) [' Liunx ', ' windows ', ' UI ', ' Python ', ' web ', ' Java ', ' PHP ']

# Deletion of the list

Create List subject = [' Liunx ', ' windows ', ' UI ', ' python ', ' web ', ' Java ', ' PHP ']

#删除指定元素subject. Remove ("PHP") #打印列表print (subject) [' Liunx ', ' Unix ', ' UI ', ' python ', ' web ', ' Java '] #根据索引删除del subject[0] #删除Liunx # printed list print (subject) [' Unix ', ' UI ', ' python ', ' web ', ' Java ']# pop default Delete last element, here Delete javasubject.pop () #打印列表 [' Unix ' , ' UI ', ' python ', ' web '] #查找某个名称的索引print (subject.index ("Python")) 2

#统计元素的个数

Create List subject = [' Liunx ', ' windows ', ' UI ', ' python ', ' web ', ' Java ', ' php ', ' python ']

Print (Subject.count ("Python")) print (subject) The inverse of the list subject.reverse () print (subject) [' Python ', ' php ', ' Java ', ' web ' , ' Python ', ' UI ', ' windows ', ' Liunx '] #列表的排序 collation according to Assci Code rules subject.sort () print (subject) [' Liunx ', ' UI ', ' Java ', ' php ', ' p Ython ', ' python ', ' web ', ' windows ']# List of Clear subject.clear () print (subject) []

Extension of the list extend

Create a list

Subject = [' Liunx ', ' windows ', ' UI ', ' python ', ' web ', ' Java ', ' php ', ' python ']

Subject2 = ["A", "B", "C"]

Subject.extend (SUBJECT2) print (subject) print (SUBJECT2) #打印列表 [' Liunx ', ' windows ', ' UI ', ' python ', ' web ', ' Java ', ' php ', ' Python ', ' A ', ' B ', ' C ' [' A ', ' B ', ' C ']

#列表的copy

  Create List   subject = ["Liunx", "Python", "web", ["C + +", "Ruby"], "Java"] 

subject = ["Liunx", "Python", "web", ["C + +", "Ruby"], "Java"] subject3 = subject.copy () # Copy subject  content # Print List print (subject) print (SUBJECT3) [' Liunx ',  ' python ',  ' web ',  [' C + + ',  ' Ruby '],  ' java ' [' Liunx ',  ' python ',  ' web ',  [' C + + ',  ' Ruby '],  ' java '] #修改   The contents of the subject  element subject[0] = "gnu liunx subject[3][0]=" C + + #打印列表print (subject) print (SUBJECT3) [ ' gnu liunx  ',  ' python ',  ' web ',  [' C + + ',  ' Ruby '],  ' java '] # subject  [' liunx ',  ' python ',  ' web ',  [' C + + ',  ' Ruby '],  ' java '] # subject  3 can see   modify subject[0] = "gnu liunx   content does not take effect in subject3 , subject[3][0]=" C + + "  This element takes effect. Shallow copy  only copy  a layer, nested part of will not be copy, just copy  the memory address inside, when subject[0] = "gnu liunx  Equivalent to re-opened a memory address, so subject3[0]  read the element content or liunx shallow copy   corresponding is a deep copy import copysubject = ["Liunx", " Python "," web ", [" C + + "," Ruby "],"Java", "PHP"] #  inside re-assigned value subject[0] = "small liunx " subject[3][0]= "C + +" subject3 =  copy.deepcopy (subject) print (subject) print (SUBJECT3) [' small liunx  ',  ' python ',  ' web ',  [' C + + ',  ' Ruby '],  ' java ',  ' PHP ' [' small liunx  ',  ' python ',  ' web ',  [' C + + ',  ' Ruby '],  ' java ',  ' PHP ']

#列表的循环取值

#创建列表 subject = ["Liunx", "Python", "web", ["C + +", "Ruby"], "Java", "PHP"]

Subject = ["Liunx", "Python", "web", ["C + +", "Ruby"], "Java", "PHP"]for i in Subject:print (i) #打印列表Liunxpythonweb [' C + + ', ' Ruby ']javaphp

The list operation for Python is now complete.

Python 3 list operations