1.元组(tuple):
元组本身是不可变数据类型,没有增删改查
元组内可以存储任意数据类型
t=(1,2.3,True,'star')
print(t)
print(type(t))
元组里面包含可变数据类型,可以间接修改元组内容
t1 = ([1,2,3],4)
t1[0].append(4) #t1[0]:元组中的第一个元素,即[1,2,3]
print(t1)
元组里如果只有一个元素的时候,后面要加逗号,否则数据类型不确定
t2 = ('hello',)
print(type(t2))
如果不加逗号:
t2 = ('hello')
print(type(t2))
2.元组的特性
1)索引
allowusers = ('root','westos','redhat')
allowpasswd = ('123','456','789')
print(allowusers[0])
print(allowusers[-1])
2)切片
print(allowusers[1:])
print(allowusers[:-1])
print(allowusers[::-1])
3)重复
print(allowusers * 3)
4)连接
print(allowusers + ('linux','python'))
5)成员操作符
print('westos' in allowusers)
print('westos' not in allowusers)
6)迭代(for循环)
for user in allowusers:
print(user)
7)枚举
for index,user in enumerate(allowusers):
print('第%d个白名单用户: %s' %(index+1,user))
for user,passwd in zip(allowusers,allowpasswd):
print(user,':',passwd)
3.元组的常用方法
t = (1,2.3,True,'linux')
1)统计出现次数
print(t.count('linux'))
2)查看索引值
print(t.index(1))
4.元组的应用场景
1)
元组的赋值,有多少个元素,就用多少个变量接收
t = ('westos',11,100)
name,age,score = t
print(name,age,score)
2)排序
1>.sort() 方法排序
scores = (100,89,45,78,65)
scoresLi = list(scores) #转换为列表
scoresLi.sort() #排序
print(scoresLi)
2>sorted() 函数排序
scores = sorted(scores)
print(scores)
3)
minscore,*middlescore,maxscore = scores #*表示可以接收多个值
print(minscore)
print(middlescore)
print(maxscore)