3.4 列表-list-切片操作

numlist=[1,2,3,4,5,6,7,8,9]
numlist[::-1] #######运行结果######[9, 8, 7, 6, 5, 4, 3, 2, 1]

numlist=[1,2,3,4,5,6,7,8,9]
numlist[::2]#######运行结果######[1, 3, 5, 7, 9]

7.列表–list-常用操作符

list1=[123,456]
list2=[456,789]
list1>list2#######运行结果######False

list3=['abc']
list4=['bcd']
list3>list4#######运行结果######False

list.count():统计出现的次数

numlist = [1,1,2,3,4,[1,2,3,5],5,6,9,8,7]
numlist.count(5)#######运行结果######1

list.index():返回第一个遇见的位置

dir(list)
numlist = [1,1,2,3,4,[1,2,3,5],5,6,9,8,7]
numlist.index(1)#######运行结果######0

list.clear():清表

numlist = [1,1,2,3,4,4,5,6,9,8,7]
numlist.clear()
print(numlist)#######运行结果######[]