python基础之元组

1、元组一级元素不能被修改，增加或删除

# 可迭代对象
tu = (123,"alex",(1,2),[12,13,45],True)
# 索引
v = tu[0]
print(v)

# 切片
v1 = tu[0:2]
print(v1)


tu1 = ("a","b","c")
v2 = "_".join(tu1)
print(v2)

>>>123

>>>(123, 'alex')
>>>a_b_c

# 可迭代对象
tu = (123,"alex",(1,2),[12,13,45],True)
# 元组是有序的  找13
print(tu[3][1])

# 元组的第一级元素不可修改
tu[3][0] = 33
print(tu)

>>>13
>>>(123, 'alex', (1, 2), [33, 13, 45], True)

# count,获取指定元素在元组中出现的次数
print(tu.count(123))
# index，
print(tu.index("alex"))

>>>1
>>>1