总结如下:
1.list的定义:
zimu=['A',"B","C","D","E","F",'G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z']
//里面的元素用单引号或者双引号都可以。
2.列表的增删改查之查:
zimu=['A',"B","C","D","E","F",'G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z']#定义一个列表
print(zimu[1])
print(zimu) #取全部
print(zimu[0:])#取全部
print(zimu[0:-1])#一直取到倒数第二个
print(zimu[3:18])#取出片段,规则:左包括,右不包括,相当于第三个(从0开始数)一直到第十七个
print(zimu[0: :2])#以步长为2来取
print(zimu[: :-1])#倒着取
zimu2=zimu[: :-1]#把取出来的片给赋给新的变量
print(zimu2)
结果如下:
2.列表的增删改查之增:
(1).append(增补)直接把新数据放到列表的最后一项
zimu=['A',"B","C","D","E","F",'G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z']#定义一个列表
zimu.append('ABC')#把'ABC'增加到列表zimu中
print(zimu)
结果如下:
(2).insert(插入)比append更灵活,可以插到任何位置
zimu=['A',"B","C","D","E","F",'G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z']#定义一个列表
zimu.insert(10,'罗亚雄') #把 '罗亚雄' 插入到 第10位
print(zimu)
结果如下:
3.列表的增删改查之改:
改(用赋值的形式来实现)
zimu=['A',"B","C","D","E","F",'G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z']#定义一个列表
zimu[3]='d' #把列表中的D改为d
print(zimu)
结果如下:
zimu=['A',"B","C","D","E","F",'G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z']#定义一个列表
zimu[0:2] =['a','b','c'] #把A B C改为小写
print(zimu)
结果如下:
4.列表的增删改查之删:
(1).remove
zimu=['A',"B","C","D","E","F",'G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z']#定义一个列表
zimu.remove('A')#删除列表中的'A', remove不能直接靠下标来删除,即zimu.remove(0)是不行的
print(zimu)
结果如下:
(2).pop
zimu=['A',"B","C","D","E","F",'G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z']#定义一个列表
a=zimu.pop(0) #删除列表中的A,pop可以靠下标来删除,并且可以返回这个删除的元素
print(zimu)
print(a)
结果如下:
(3).del不是列表内置删除,它是通用的,直接删除对应元素就好
del zimu[0] #del不是列表内置删除,它是通用的,直接删除对应元素就好
print(zimu)
结果如下:
列表list的其他操作:
1:count,用来数列表中某个元素出现的次数
t=['to','be','or','not','to','be'].count('to')
print(t)
结果如下:
2: extend用来把一个列表添加另一个列表中
#2: extend,用来把一个列表添加另一个列表中
a = [1,2,3,'jkk']
b = [4,5,6]
a.extend(b)
b.extend(a)
print(a)
print(b)
结果如下:
3:index找到列表中某元素的位置
zimu=['A',"B","C","D","E","F",'G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z']#定义一个列表
print(zimu.index('J'))#找到列表子母中 J 的位置
4.sort(排序)按ASCII里的顺序来排序的
x = [3,2,4,6,54,3,34]
x.sort()
print(x)
结果如下:
有点多,留了一个购物的作业明天做!坚持!