1. 元组——tuple(元组是一个只读的list)

(1) 元组的定义

注意：定义单个元素的元组，在元素后面要加上 ','

(2) 元组也支持嵌套

(3) 下标索引取出元素

(4) 元组的相关操作

        1. index——查看元组中某个元素在元组中的位置从左到右第一次出现的位置

t1 = ("abc", "123", "123", "afg", "doinb")
tmp_pos = t1.index("doinb")
print(f"123 position is {tmp_pos}")

        2. count——查看元组中某个元素在整个元组中的数量

t1 = ("abc", "123", "123", "afg", "doinb")
tmp_num = t1.count("123")
print(f"123 num is {tmp_num}")

        3. len——查看元组中所有元素的个数

t1 = ("abc", "123", "123", "afg", "doinb")
tmp_len = len(t1)
print(f"t1 num is {tmp_len}")

        4. while循环遍历元组

t1 = ("abc", "123", "123", "afg", "doinb")
tmp_cnt = 0
while tmp_cnt < len(t1):print(f"{t1[tmp_cnt]}")tmp_cnt += 1

        5. for循环遍历元组

t1 = ("abc", "123", "123", "afg", "doinb")
for i in t1:print(f"{i}")

(5) 注意：

        1. 元组中的内容不可修改，但元组中嵌套的列表可以修改

t1 = ("abc", "123", "123", "afg", ["1", "2", "3"])
for i in t1:print(f"{i}")t1[4][1] = "324"
for i in t1:print(f"{i}")

        2. 元组与列表特性基本相同，但内容不可修改

(6) 总结

(7) 练习

t1 = ('周杰伦', 11, ['football', 'music'])
age_index = t1.index(11)
print(f"age index is {age_index}")
name_index = t1.index('周杰伦')
print(f"name_index is {name_index}")
t1[2].remove('football')
print(t1)
t1[2].append('coding')
print(t1)