【Python3】基本数据类型-元祖(

发布时间:2019-10-17 09:07:22编辑:auto阅读(130)

    元组(tuple)

    元祖为不可被修改的列表,不可变类型

    基本操作:

    • 索引

    • 切片

    • 循环

    • 长度

    • 包含

    以下为详细介绍 ~

    count 查找元素个数

    user_tuple = ('xmzncc','asd','fcc')
    v = user_tuple.count('xmzncc')
    print(v)

    index 获取元祖中第一个元素的索引位置

    user_tuple = ('xmzncc','asd','fcc','xmzncc')
    v = user_tuple.index('xmzncc')
    print(0)

    字典(dict)

    get 根据key值去对应的value
    取不到值返回None,不报错

    dic = {'k1':'v1','k2':'v2'}
    v = dic.get('k1')
    print(v)

    clear 清空

    dic = {'k1':'v1','k2':'v2'}
    v = dic.clear()
    print(dic)

    copy 拷贝(浅拷贝)

    dic = {'k1':'v1','k2':'v2'}
    v = dic.copy()
    print(dic)

    pop 删除并获取对应的value值

    dic = {'k1':'v1','k2':'v2'}
    v = dic.pop('k1')
    print(dic)
    print(v)

    popitem 随机删除键值对,并获取到删除的键值

    dic = {'k1':'v1','k2':'v2'}
    v = dic.popitem()
    print(v)
    print(dic)

    setdefault 增加,如果key值存在则不操作

    dic = {'k1':'v1','k2':'v2'}
    dic.setdefault('k3','v3')
    print(dic)

    update 批量增加或修改

    dic = {'k1':'v1','k2':'v2'}
    dic.update({'k3':'v3','k4':'v4'})
    print(dic)

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