• ⑧python列表、元组


    一、列表

    举例说明列表的各种操作

    person = ["p1","p2","p3","p4","p5","p6","p7","p8","p9","p10"]
    person2 = [1,2,3,4]
    
    print(person[0],person[2]) #取出p1,p3
    print(person[0:4]) #顾头不顾尾:列表里从零开始数,取出第0、1、2、3,四个值,第4不取,也即p5不取
    print(person[5:8]) #顾头不顾尾:列表里从零开始数,取第5、6、7
    print(person[-1])  #取列表中最后一个值
    print(person[-5:]) #取列表中最后五个值
    print(person[0:-1:2])#从第一个值开始,隔一个一取
    print(person.index("p6")) #取p6的位置
    print(person[person.index("p6")])
    print(person.count("p7")) #该值在列表中的数量'''
    person.clear()    #清空列表
    person.reverse()  #翻转列表中的值
    person.sort()     #给列表中的值排序
    person.extend(person2) #合并person和person2,并不删除person2
    del person2        #删掉列表
    
    person.append("zhuijia") #追加到列表中的最后
    person.insert(2,"charu") #插入到列表中2的位置
    person[5] = ("xiugai")   #修改位置5的值
    person.remove("p7")      #删除该值
    del person[7]            #删除该位置7的值
    person.pop()             #删除列表中最后一个值
    person.pop(1)            #删除该位置1的值
    
    print(person)
    print(person2)

    浅copy

    person = ["p1","p2","p3","p4","p5","p6","p7",["salary",1000],"p8","p9","p10"]
    
    person2 = person.copy() #浅copy,只copy第一层,子列表不copy
    person3 = person[:] #第二种方式
    person4 = list(person) #第三种方式 person[3] = "zhongwen" person[7][0]="Salary" print(person) print(person2) 结果: ['p1', 'p2', 'p3', 'zhongwen', 'p5', 'p6', 'p7', ['Salary', 1000], 'p8', 'p9', 'p10'] ['p1', 'p2', 'p3', 'p4', 'p5', 'p6', 'p7', ['Salary', 1000], 'p8', 'p9', 'p10']

     深copy

    import copy
    person = ["p1","p2","p3","p4","p5","p6","p7",["salary",1000],"p8","p9","p10"]
    
    #person2 = person.copy() #浅copy,只copy第一层,子列表不copy
    person2 = copy.deepcopy(person) #深copy,所有都copy
    person[3] = "zhongwen"
    person[7][0]="Salary"
    
    print(person)
    print(person2)
    结果:
    ['p1', 'p2', 'p3', 'zhongwen', 'p5', 'p6', 'p7', ['Salary', 1000], 'p8', 'p9', 'p10']
    ['p1', 'p2', 'p3', 'p4', 'p5', 'p6', 'p7', ['salary', 1000], 'p8', 'p9', 'p10']

     列表循环

    person = ["p1","p2","p3","p4","p5","p6","p7",["salary",1000],"p8","p9","p10"]
    for i in person:
        print(i)
    结果:
    p1
    p2
    p3
    p4
    p5
    p6
    p7
    ['salary', 1000]
    p8
    p9
    p10

     二、元组

    元组其实跟列表差不多,也是存一组数,只不过它一旦被创建,便不能在修改,所以又叫只读列表

    它只有两个方法一个是count,一个是index

    person = ("p1","p2","p3","p4","p5","p6","p7","p8","p9","p10")
    person2 = ("o1","o2","o3","o4")
    
    print(person[0],person[2]) #取出p1,p3
    print(person[0:4]) #顾头不顾尾:列表里从零开始数,取出第0、1、2、3,四个值,第4不取,也即p5不取
    print(person[5:8]) #顾头不顾尾:列表里从零开始数,取第5、6、7
    print(person[-1])  #取列表中最后一个值
    print(person[-5:]) #取列表中最后五个值
    print(person.index("p6")) #取p6的位置
    print(person[person.index("p6")])
    print(person.count("p7")) #该值在列表中的数量
    del person2        #删掉列表
    #列表循环
    for i in person:
        print(i)
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  • 原文地址:https://www.cnblogs.com/pengp/p/6613463.html
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