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  • 06列表的常用基本操作

    基本数据类型列表list(增删改查)
    •list 专门是用来存储大量的数据的数据类型
    •在python中使用[]中括号来表示列表
    •列表是可变的数据类型,内部元素没有任何要求
    •列表: 能装东西的东西

    lis = ["张三","李四","wangwu",{1,2,3},["uan","gpc"]]
    print (lis)
    

    [‘张三’, ‘李四’, ‘wangwu’, {1, 2, 3}, [‘uan’, ‘gpc’]]
    添加元素
    •append()追加
    •insert()插入
    •extend()迭代添加

    # 1 添加元素
    # append()追加
    
    a = ["唐僧","沙悟净","猪八戒"]
    print (a)
    a.append("孙悟空")
    print(a)
    

    [‘唐僧’, ‘沙悟净’, ‘猪八戒’]
    [‘唐僧’, ‘沙悟净’, ‘猪八戒’, ‘孙悟空’]

    # 2,插入 insert()
    a = ["唐僧","沙悟净","猪八戒"]
    print(a)
    a.insert(1,"孙悟空")
    print(a)
    

    [‘唐僧’, ‘沙悟净’, ‘猪八戒’]
    [‘唐僧’, ‘孙悟空’, ‘沙悟净’, ‘猪八戒’]

    # 迭代添加 extend ()
    a = ["唐僧","沙悟净","猪八戒"]
    print(a)
    a.extend(["孙悟空","白龙马"])
    print(a)
    a.extend("葛鹏程")
    print(a)
    

    [‘唐僧’, ‘沙悟净’, ‘猪八戒’]
    [‘唐僧’, ‘沙悟净’, ‘猪八戒’, ‘孙悟空’, ‘白龙马’]
    [‘唐僧’, ‘沙悟净’, ‘猪八戒’, ‘孙悟空’, ‘白龙马’, ‘葛’, ‘鹏’, ‘程’]

    删除元素
    •remove()删除一个元素
    •pop(1) 索引指标删除0,1,2,3 当()括号为空时默认删除最后一个
    •clear() 清空
    •del删除

    a = ["唐僧","沙悟净","猪八戒","孙悟空","白龙马"]
    print (a)
    a.remove("唐僧")
    print (a)
    a.remove("如来")#字符不存在就报错
    print (a)
    

    [‘唐僧’, ‘沙悟净’, ‘猪八戒’, ‘孙悟空’, ‘白龙马’]
    [‘沙悟净’, ‘猪八戒’, ‘孙悟空’, ‘白龙马’]


    ValueError Traceback (most recent call last)
    in
    3 a.remove(“唐僧”)
    4 print (a)
    ----> 5 a.remove(“如来”)#字符不存在就报错
    6 print (a)

    ValueError: list.remove(x): x not in list

    a = ["唐僧","沙悟净","猪八戒","孙悟空","白龙马"]
    print (a)
    a.pop()
    print (a)
    a.pop(1)
    print (a)
    
    

    [‘唐僧’, ‘沙悟净’, ‘猪八戒’, ‘孙悟空’, ‘白龙马’]
    [‘唐僧’, ‘沙悟净’, ‘猪八戒’, ‘孙悟空’]
    [‘唐僧’, ‘猪八戒’, ‘孙悟空’]

    a = ["唐僧","沙悟净","猪八戒","孙悟空","白龙马"]
    print (a)
    a.clear()
    print (a)
    

    [‘唐僧’, ‘沙悟净’, ‘猪八戒’, ‘孙悟空’, ‘白龙马’]
    []

    a = ["唐僧","沙悟净","猪八戒","孙悟空","白龙马"]
    print (a)
    del a[0]
    print (a)
    

    [‘唐僧’, ‘沙悟净’, ‘猪八戒’, ‘孙悟空’, ‘白龙马’]
    [‘沙悟净’, ‘猪八戒’, ‘孙悟空’, ‘白龙马’]

    修改
    •列表通过索引修改

    a = ["唐僧","沙悟净","猪八戒","孙悟空","白龙马"]
    print (a)
    a[0]="如来"
    print(a)
    

    [‘唐僧’, ‘沙悟净’, ‘猪八戒’, ‘孙悟空’, ‘白龙马’]
    [‘如来’, ‘沙悟净’, ‘猪八戒’, ‘孙悟空’, ‘白龙马’]

    a = ["唐僧","沙悟净","猪八戒","孙悟空","白龙马"]
    print (a)
    a[1:3]=["如来"]
    print(a)
    

    [‘唐僧’, ‘沙悟净’, ‘猪八戒’, ‘孙悟空’, ‘白龙马’]
    [‘唐僧’, ‘如来’, ‘孙悟空’, ‘白龙马’]

    a = ["唐僧","沙悟净",["马化腾","ma云","葛鹏程"],"猪八戒","孙悟空","白龙马"]
    a[2][1] = "马云"
    print(a)
    

    [‘唐僧’, ‘沙悟净’, [‘马化腾’, ‘马云’, ‘葛鹏程’], ‘猪八戒’, ‘孙悟空’, ‘白龙马’]

    a = ["唐僧","沙悟净",["马化腾","ma云","葛鹏程"],"猪八戒","孙悟空","白龙马"]
    a[2][1] = a[2][1].replace("ma","马")
    print(a)
    

    [‘唐僧’, ‘沙悟净’, [‘马化腾’, ‘马云’, ‘葛鹏程’], ‘猪八戒’, ‘孙悟空’, ‘白龙马’]

    查询
    •列表通过索引和切片进行查询
    •使用for循环进行查询

    a = ["唐僧","沙悟净","猪八戒","孙悟空","白龙马"]
    print (a)
    print(a[2::2])
    print (a[1])
    print(a[::-2])
    

    [‘唐僧’, ‘沙悟净’, ‘猪八戒’, ‘孙悟空’, ‘白龙马’]
    [‘猪八戒’, ‘白龙马’]
    沙悟净
    [‘白龙马’, ‘猪八戒’, ‘唐僧’]

    a = ["唐僧","沙悟净","猪八戒","孙悟空","白龙马"]
    for b in a:
        print (b)
    

    唐僧
    沙悟净
    猪八戒
    孙悟空
    白龙马

    a = ["唐僧","沙悟净","猪八戒","孙悟空","白龙马"]
    for b in a:
        for c in b:
            print (c)
    














    a = ["唐僧","沙悟净","猪八戒","孙悟空","白龙马"]
    print (a[3][0])
    

    a = ["唐僧","沙悟净",["马化腾","马云","葛鹏程"],"猪八戒","孙悟空","白龙马"]
    print (a[2][0])
    print (a[2][0][1])
    

    马化腾

    # range 数数
    for i in range (0,11):
        print (i)
    

    0
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10

    for i in range (10):
        print ("我爱你",i)
    

    我爱你 0
    我爱你 1
    我爱你 2
    我爱你 3
    我爱你 4
    我爱你 5
    我爱你 6
    我爱你 7
    我爱你 8
    我爱你 9

    a = ["唐僧","沙悟净","马化腾","马云","葛鹏程","猪八戒","孙悟空","白龙马"]
    for b in range(len(a)):
        print (a[b])
    

    唐僧
    沙悟净
    马化腾
    马云
    葛鹏程
    猪八戒
    孙悟空
    白龙马

    a = ["唐僧",",,","沙悟净","马化腾","马云","葛鹏程","猪八戒","孙悟空","白龙马"]
    print(a)
    a[1]=a[0]
    print (a)
    

    [‘唐僧’, ‘,’, ‘沙悟净’, ‘马化腾’, ‘马云’, ‘葛鹏程’, ‘猪八戒’, ‘孙悟空’, ‘白龙马’]
    [‘唐僧’, ‘唐僧’, ‘沙悟净’, ‘马化腾’, ‘马云’, ‘葛鹏程’, ‘猪八戒’, ‘孙悟空’, ‘白龙马’]

    # 3,replace ( ) 字符串替换
    test = "我 、喜 、欢 打  游戏"
    print(test)
    test1=test.replace("游戏","看书")
    print (test1)
    test2 = test.replace(" ","")  #去掉所有空格
    print (test2)
    test2 = test.replace("、","
    ") 
    print (test2)
    

    我 、喜 、欢 打 游戏
    我 、喜 、欢 打 看书
    我、喜、欢打游戏


    欢 打 游戏

    a = ["呵呵","哈哈","嘻嘻","嘿嘿"]
    b = ["3","4","5","6"]
    d = ["呵呵11","哈哈11","嘻嘻11","嘿嘿11"]
    c =[]
    c.extend(d)
    for i in range (4):
    
        text =a [i]
        times=int(b[i])
    
        for time in range(times):
            gpc1 = (text+str(time+1))
            c.append(gpc1)
            
    
    print(c)    
    

    [‘呵呵11’, ‘哈哈11’, ‘嘻嘻11’, ‘嘿嘿11’, ‘呵呵1’, ‘呵呵2’, ‘呵呵3’, ‘哈哈1’, ‘哈哈2’, ‘哈哈3’, ‘哈哈4’, ‘嘻嘻1’, ‘嘻嘻2’, ‘嘻嘻3’, ‘嘻嘻4’, ‘嘻嘻5’, ‘嘿嘿1’, ‘嘿嘿2’, ‘嘿嘿3’, ‘嘿嘿4’, ‘嘿嘿5’, ‘嘿嘿6’]

    # 迭代添加 extend ()
    a = ["唐僧","沙悟净","猪八戒"]
    print(a)
    a.extend(["孙悟空","白龙马"])
    print(a)
    

    [‘唐僧’, ‘沙悟净’, ‘猪八戒’]
    [‘唐僧’, ‘沙悟净’, ‘猪八戒’, ‘孙悟空’, ‘白龙马’]

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  • 原文地址:https://www.cnblogs.com/gemoumou/p/13635359.html
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