• python列表命令


    创建普通列表:member;; 创建混合列表:mix; 创建空列表:empty  

    >>> member = ['lala','oo']
    >>> member
    ['lala', 'oo']
    >>> member.append('jjj')
    >>> member
    ['lala', 'oo', 'jjj']
    >>> len(member)
    3
    >>> member.extend(['xx','pp'])
    >>> member
    ['lala', 'oo', 'jjj', 'xx', 'pp']
    >>> len	(member )
    5
    >>> member .insert(0,'ll')
    >>> member
    ['ll', 'lala', 'oo', 'jjj', 'xx', 'pp']
    >>> 
    

      

    append()只能添加一个

    extend() 扩展一个列表

    insert()排列或插入,排序要从0开始

    从列表中获取元素

    通过元素的索引值(index)从列表中获取单个元素,从0开始

    用temp可以改变位置

    >>> member
    ['ll', 'lala', 'oo', 'jjj', 'xx', 'pp']
    >>> member [0]
    'll'
    >>> temp  = member [0]>>> member [0] = member [1]
    >>> member
    ['lala', 'lala', 'oo', 'jjj', 'xx', 'pp']
    >>> member [1] = temp
    >>> member
    ['lala', 'll', 'oo', 'jjj', 'xx', 'pp']
    >>> 

    从列表删除元素

    1:remove()

    2:del 

    3:pop() 从列表中取出一个元素

    >>> member
    ['lala', 'll', 'oo', 'jjj', 'xx', 'pp']
    >>> member.remove ('ll')
    >>> member
    ['lala', 'oo', 'jjj', 'xx', 'pp']>>> del member [1]
    >>> member
    ['lala', 'jjj', 'xx', 'pp']
    >>> member .pop()
    'pp'
    >>> member
    ['lala', 'jjj', 'xx']
    >>> name = member .pop()
    >>> name
    'xx'
    >>> member
    ['lala', 'jjj']
    >>> member .pop(1)
    'jjj'
    >>> member
    ['lala']

    利用列表分片:slice

    >>> member [1:3]

    1代表开始,3代表结束 0:可以不用写 最后也可以不用写,  都不写可以拷贝文件

    >>> member
    ['小耿哥', '耿哥 ', 'lala', 'haha']
    >>> member [1:3]
    ['耿哥 ', 'lala']
    >>> member
    ['小耿哥', '耿哥 ', 'lala', 'haha']
    >>> member [:3]
    ['小耿哥', '耿哥 ', 'lala']
    >>> member [:]
    ['小耿哥', '耿哥 ', 'lala', 'haha']
    >>> member2 = member [:]
    >>> member2
    ['小耿哥', '耿哥 ', 'lala', 'haha']

    列表常用操作符

    1:比较操作符

    2:逻辑操作符

    3:连接操作符

    4:重复操作符

    5:成员关系操作符

    >>> list1 = [123,234]
    >>> list2 = [345,456]
    >>> list1 > list2
    False
    >>> list3 = [123,234]
    >>> (list1 < list2) and (list1 == list3)
    True
    >>> list4 = list1 + list3
    >>> list4
    [123, 234, 123, 234]
    >>> 不能添加新元素
    >>> list3 * 3
    [123, 234, 123, 234, 123, 234]
    >>> list3 *= 3
    >>> list3
    [123, 234, 123, 234, 123, 234]
    >>> 123 in list3
    True
    >>> list5 = [123,['小耿哥'],456]
    >>> '小耿哥' in list5[1]
    True
    >>> '用索引号去访问列表的值'
    '用索引号去访问列表的值'
    >>> list5[1][0]
    '小耿哥'

    列表的小伙伴

    count:计算参数在列表的次数

    index:索引

    reverse:逆行

    sort:指定方式排序

    >>> list3.count(123)
    3
    >>> list3.index(123)
    0
    >>> list3.index(123,3,7)
    4
    >>> list3.reverse()
    >>> list3
    [234, 123, 234, 123, 234, 123]
    >>> list6 = [4,3,6,4,98,54,54,41]
    >>> list6.sort()
    >>> list6.sort()
    >>> list6]
    SyntaxError: invalid syntax
    >>> list6
    [3, 4, 4, 6, 41, 54, 54, 98]
    >>> list6.sort(reverse=True)
    >>> list6
    [98, 54, 54, 41, 6, 4, 4, 3]

    元组:不可以被修改

    元组跟列表很相似

    >>> tuple1 = (1,2,3,4,5,6,7,8)
    >>> tuple1
    (1, 2, 3, 4, 5, 6, 7, 8)
    >>> tuple1[1]
    2
    >>> tuple1[5:]
    (6, 7, 8)
    >>> tuple2 = tuple1[:]
    >>> tuple2
    (1, 2, 3, 4, 5, 6, 7, 8)
    >>> temp = (1)
    >>> temp
    1
    >>> temp2 = 2,3,4
    >>> type(temp2)
    <class 'tuple'>
    >>> type(temp)
    <class 'int'>
    >>> 8 * (8)
    64
    >>> 8 * (8,)
    (8, 8, 8, 8, 8, 8, 8, 8)
    >>> '跟逗号有关'
    '跟逗号有关'
    >>> temp = ('小耿哥','古风歌','耿哥','哈哈啊')
    >>> temp
    ('小耿哥', '古风歌', '耿哥', '哈哈啊')
    >>> temp = temp[:2] + ('啦啦',) + temp[2:]
    >>> temp
    ('小耿哥', '古风歌', '啦啦', '耿哥', '哈哈啊')
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  • 原文地址:https://www.cnblogs.com/xpl520/p/11245242.html
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