python中的元组

元组

1.元组与列表类似，里面的元素用","号隔开，使用小括号 

2.元组里面的数据不可修改

tuple = (1,2,3,4,'b')

修改元组中的元素，不可修改

tuple = (1,2,3,4,'b')
tuple[0]=0
print(tuple)

结果：
Traceback (most recent call last):
  File "/Users/mahong/Desktop/study/Auto_Python/day2/元组.py", line 11, in <module>
    tuple[0]=0
TypeError: 'tuple' object does not support item assignment

当元组中只有一个元素时，需要在后面加上逗号',',否则会被当成运算符使用

tuple1 = (1)
print(type(tuple1))

tuple2 = (1,)
print(type(tuple2))

输出:
<class 'int'>
<class 'tuple'>

访问元组,同样遵循顾头不顾尾的规则

tuple = (1,2,3,4,'b')
print(tuple[1:3])

输出:
(2, 3)

删除元组，不能删除元组中的元素，只能删除整个元组

tp = (1,2,3,4,'b')
print(tp)
del tp
print(tp)

输出:
(1, 2, 3, 4, 'b')
Traceback (most recent call last):
  File "/Users/mahong/Desktop/study/Auto_Python/day2/元组.py", line 13, in <module>
    print(tp)
NameError: name 'tp' is not defined

内置方法：len(tuple),列表转元组tuple(list)

tp = (1,2,3,4,'b')
print(len(tp))
L1 = ['a','b','c','d','e']
tuple(L1)
print(tuple(L1))


输出:
5
('a', 'b', 'c', 'd', 'e')