Python基础数据类型tuple元组的概念与用法

var = (1, 2, 3)
var = ("1", "2", "3")
var = (True, False)
var = (1.1, 1.11, 1.111)
var = ((1,), (2, 3), (4, 5))
var = ([1, 2], {"name": "polo"})

lis = [1, 2, 3]
lis[0] = 111
print(lis)

tupl = (1, 2, 3)
tupl[0] = 2


# 输出结果
Traceback (most recent call last):
  File "/Users/polo/Documents/pylearn/第一章:python 基本类型/6_tuple元组.py", line 21, in <module>
    tupl[0] = 2
TypeError: 'tuple' object does not support item assignment

# 空
tup = ()
print(tup, type(tup))


# 输出结果
() <class 'tuple'>

# 只包含一个元素
tup = (1)
print(tup, type(tup))


# 输出结果
1 <class 'int'>

# 正确
tup = (1,)
print(tup, type(tup))


# 输出结果
(1,) <class 'tuple'>

# 等价写法
a = 1, 2
print(a, type(a))
a = (3, 4)
print(a, type(a))

a = 1,
print(a, type(a))
a = (3,)
print(a, type(a))


# 输出结果
(1, 2) <class 'tuple'>
(3, 4) <class 'tuple'>
(1,) <class 'tuple'>
(3,) <class 'tuple'>

# 索引
tup = [1, 2, 3, 4, 5]
print(tup[0])
print(tup[-1])
print(tup[2])


# 输出结果
1
5
3

# 切片
tup = [1, 2, 3, 4, 5, 6, 7, 8]
print(tup[:])  # 取全部元素
print(tup[0:])  # 取全部元素
print(tup[2:5])  # 取第 3 个元素到第 5 个元素
print(tup[::-1])  # 倒序取所有元素
print(tup[-3:-1])  # 取倒数第 3 个元素到倒数第 2 个元素


# 输出结果
[1, 2, 3, 4, 5, 6, 7, 8]
[1, 2, 3, 4, 5, 6, 7, 8]
[3, 4, 5]
[8, 7, 6, 5, 4, 3, 2, 1]
[6, 7]

# +
tup1 = (1,)
tup2 = (2, 3)
print(tup1 + tup2)


# 输出结果
(1, 2, 3)

# *
tup = (1, 2)
print(tup * 2)


# 输出结果
(1, 2, 1, 2)

# in
tup = (1, 2, 3)
print(1 in tup)
print(22 not in tup)


# 输出结果
True
True

# len
tup = (1, 2, 3)
print(len(tup))


# 输出结果
3

# max
tup = (1, 2, 3)
print(max(tup))


# 输出结果
3

# min
tup = (1, 2, 3)
print(min(tup))


# 输出结果
1

# index
tup = (1, 2, 3)
print(tup.index(1))
print(tup.index(11))


# 输出结果
0
Traceback (most recent call last):
  File "/Users/Documents/pylearn/第一章:python 基本类型/6_tuple元组.py", line 88, in <module>
    print(tup.index(11))
ValueError: tuple.index(x): x not in tuple

# count
tup = (1, 2, 1)
print(tup.count(1))
print(tup.count(11))


# 输出结果
2
0