一、列表概念
存储、处理一组元素的数据结构,列表内可包含多个数字或字符。
创建列表
列表名 = [元素1,元素2,……]
1 >>>left_all = [1,9] 2 >>>height_all = [6,10] 3 等同于 4 >>>left_1 = 1 5 >>>left_2 = 9 6 >>>height_1 = 6 7 >>>height_2 = 10
二、列表取值
1 >>> a = ['001','马云','male','1234857456'] 2 >>> print a[0] 3 001 4 >>> print a[1] 5 马云 6 #取指定范围的一组元素时,包头不包尾 7 >>> print a[2:3] 8 ['male'] 9 >>> print a[2:4] 10 ['male', '1234857456'] 11 >>> print a[5:7] 12 [] 13 #取值前几位也可以这么写 14 >>> print a[:3] 15 ['001','马云','male'] 16 #取值后几位可以这么写 17 >>> print a[-1] 18 ['1234857456'] 19 >>> print a[-2] 20 ['male'] 21 >>> print a[-2:-1] 22 ['male'] 23 >>> print a[-2:] 24 ['male','1234857456'] 25 #分片切割取值 26 >>> name=['zhangsan','lisi','wangwu',22,9,23,3,4,5,7,87,89,9,9,4] 27 >>> name[:6] 28 ['zhangsan','lisi','wangwu','22','9','23'] 29 >>>name[:6][2:4] 30 ['wangwu','22'] 31 >>> name[:6][2:4][0] 32 'wangwu' 33 >>> name[:6][2:4][0][1] 34 'w'
三、修改列表
1 >>> a = ['001','马云','male','1234857456'] 2 >>>a[2] = 'female' 3 >>>print a[2] 4 >>>female
四、添加元素
1 #以下代码在列表最后添加字符串'PBY' 2 >>> a = ['001','马云','male','1234857456'] 3 >>> a.append('PBY') 4 >>> print a[4] 5 PBY 6 #以下代码在列表中的第二个位置插入字符串'35' 7 >>> a = ['001','马云','male','1234857456'] 8 >>>a.insert(2,'35') 9 >>>print a[2:4] 10 ['35','male']
五、删除元素
1 >>> a = ['001','马云','male','1234857456'] 2 >>>del a[1] 3 >>>print a 4 ['001','male','1234857456']
用函数方法也可以删除
1 >>> a.remove('马云') 2 >>> print name 3 >>> ['001','male','1234857456']
六、列表查找操作
查找列表中是否存在指定的数值
元素值 in 列表名
返回布尔类型 True 或False
1 >>> a = ['001','马云','male','1234857456'] 2 >>>'马云' in a 3 True
七、列表合并
用 + 连接两个列表
1 >>>a1=['you','are'] 2 >>>a2=['a','pig'] 3 >>>a=a1+a2 4 >>> print a 5 ['you','are','a','pig']
八、列表重复
1 >>>a = ['I','love','you'] 2 >>>a10 = a*3 3 >>>print a10 4 ['I','love','you','I','love','you','I','love','you'
九、列表相关练习
用变量num保存数值76,调用count()函数,查询num变量在score列表中出现的次数
1 >>> score=[1,76,34,76,18] 2 >>> num=76 3 >>> score.count(num) 4 2