1、元组的创建
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 = (1,2,3,4,True,'red')
print(type(t))
print(t)
###元组里面包含可变数据类型,可以间接修改元组的内容
t = ([1,2,3],4)
print(t)
t[0].append(4)
print(t)
###元组中如果只有一个元素的时候,后面必须加逗号,否则类型不确定
t = ('hello')
t1 = ('hello',)
t2 = (1,)
print(t)
print(type(t))
print(t1)
print(type(t1))
print(t2)
print(type(t2))
2、元组的特性
1、索引:下标运算符[]
t = ('red','blue','green')
print(t[1])
2、切片:元组截取[start:end]
t = ('red','blue','green')
print(t[:-1])
print(t[1:])
print(t[:-1])
print(t[::-1])
3、重复:*运算符
t = ('red','blue','green')
print(t * 2)
4、连接:+运算符
t = ('red','blue','green')
print(t + ('blak','gray'))
5、成员操作符:in 和 not in
t = ('red','blue','green')
print('red' in t)
print('black' in t)
6、for循环
t = ('red','blue','green')
for i in t:
print(i)
###zip:将各元组的元素之间一一对应
t = ('red','blue','green')
t1 = ('1','2','3')
for i,j in zip(t,t1):
print(i,':',j)
3、元组常用方法
统计某个元素出现次数:count
查看指定元素的下标:index
t = ('red','blue','green','red')
print(t.count('red'))
print(t.index('blue'))
4、元组的应用
1、交换变量的值
a = 1
b = 2
print(a)
print(b)
b,a = a, b
print('After change:')
print('a = %d b = %d' %(a,b))
2、打印变量的值
user = 'root'
passwd = '123'
t = (user,passwd)
print('user:%s passwd:%s' %(user,passwd))
print(('user:%s passwd:%s')%t)
3、元组的赋值,有多少元素,就使用多少变量接收
t = ('student','23','male')
id,age,sex = t
print(id,age,sex)