python基础-set、各个数据类型转换、深浅拷贝

转换

x=dict([("x",1),("y",2)])
print(x)

{'x': 1, 'y': 2}

set集合

set = {3,"Braay",True,(1,2,4)}
print(set)
print("---------#集合的增--")
set1 = {'alex','wusir','ritian','egon','barry'}
set1.add('景女神')
print(set1)

#update：迭代着增加
set1.update('A')
print(set1)
set1.update('老师')
print(set1)
set1.update([1,2,3])
print(set1)

print("---------集合的删---")
#3，集合的删。
set1 = {'alex','wusir','ritian','egon','barry'}

set1.remove('alex')  # 删除一个元素
print(set1)

set1.pop()  # 随机删除一个元素
print(set1)

set1.clear()  # 清空集合
print(set1)

# del set1  # 删除集合
# print(set1)

print("############交集#####")

set1 = {1,2,3,4,5}
set2 = {4,5,6,7,8}
print(set1 & set2)  # {4, 5}
print(set1.intersection(set2))  # {4, 5}

print("############并集#####")
set1 = {1,2,3,4,5}
set2 = {4,5,6,7,8}
print(set1 | set2)  # {1, 2, 3, 4, 5, 6, 7}
print(set2.union(set1))  # {1, 2, 3, 4, 5, 6, 7}

print("############差集。（- 或者 difference）#####")
set1 = {1,2,3,4,5}
set2 = {4,5,6,7,8}
print(set1 - set2)  # {1, 2, 3}
print(set1.difference(set2))  # {1, 2, 3}

print("###########反交集#####")
set1 = {1,2,3,4,5}
set2 = {4,5,6,7,8}
print(set1 ^ set2)  # {1, 2, 3, 6, 7, 8}
print(set1.symmetric_difference(set2))  # {1, 2, 3, 6, 7, 8}

print("###########子集与超集#####")
set1 = {1,2,3}
set2 = {1,2,3,4,5,6}

print(set1 < set2)
print(set1.issubset(set2))  # 这两个相同，都是说明set1是set2子集。

print(set2 > set1)
print(set2.issuperset(set1))  # 这两个相同，都是说明set2是set1超集。

print("######frozenset不可变集合，让集合变成不可变类型,没有增加操作#####")
s = frozenset('barry')
prin`
(s,type(s))  # frozenset({'a', 'y', 'b', 'r'}) <class 'frozenset'>

E:\python\python_sdk\python.exe E:/python/py_pro/demo.py
{True, 3, 'Braay', (1, 2, 4)}
---------#集合的增--
{'alex', 'barry', '景女神', 'ritian', 'wusir', 'egon'}
{'alex', 'A', 'barry', '景女神', 'ritian', 'wusir', 'egon'}
{'alex', 'A', 'barry', '老', '景女神', 'ritian', 'wusir', '师', 'egon'}
{1, 2, 3, 'alex', 'A', 'barry', '老', '景女神', 'ritian', 'wusir', '师', 'egon'}
---------集合的删---
{'barry', 'ritian', 'wusir', 'egon'}
{'ritian', 'wusir', 'egon'}
set()
############交集#####
{4, 5}
{4, 5}
############并集#####
{1, 2, 3, 4, 5, 6, 7, 8}
{1, 2, 3, 4, 5, 6, 7, 8}
############差集。（- 或者 difference）#####
{1, 2, 3}
{1, 2, 3}
###########反交集#####
{1, 2, 3, 6, 7, 8}
{1, 2, 3, 6, 7, 8}
###########子集与超集#####
True
True
True
True
######frozenset不可变集合，让集合变成不可变类型,没有增加操作#####
frozenset({'b', 'a', 'r', 'y'}) <class 'frozenset'>

Process finished with exit code 0

深浅copy

#先看赋值运算。
l1 = [1,2,3,["aa","bb"]]
l2 = l1

print(l1)
print(l2)

l1[0] = 111
print(l1)
print(l2)

#对于赋值运算来说，l1与l2指向的是同一个内存地址，所以他们是完全一样的。
l1[3][0] = "wusir"
print(l1)
print(l2)

#浅拷贝copy
# 对于浅copy来说，第一层创建的是新的内存地址
# 而从第二层开始，指向的都是同一个内存地址
# 所以，对于第二层以及更深的层数来说，保持一致性
print("---------------------")
l1 = [1, 2, 3, ['barry', 'alex']]
l2 = l1.copy()
print(l1, id(l1))  # [1, 2, 3, ['barry', 'alex']] 2380296895816
print(l2, id(l2))  # [1, 2, 3, ['barry', 'alex']] 2380296895048
l1[1] = 222
print(l1, id(l1))  # [1, 222, 3, ['barry', 'alex']] 2593038941128
print(l2, id(l2))  # [1, 2, 3, ['barry', 'alex']] 2593038941896

l1[3][0] = 'wusir'
print(l1, id(l1[3]))  # [1, 2, 3, ['wusir', 'alex']] 1732315659016
print(l2, id(l2[3]))  # [1, 2, 3, ['wusir', 'alex']] 1732315659016

E:\python\python_sdk\python.exe E:/python/py_pro/demo.py
[1, 2, 3, ['aa', 'bb']]
[1, 2, 3, ['aa', 'bb']]
[111, 2, 3, ['aa', 'bb']]
[111, 2, 3, ['aa', 'bb']]
[111, 2, 3, ['wusir', 'bb']]
[111, 2, 3, ['wusir', 'bb']]
---------------------
[1, 2, 3, ['barry', 'alex']] 44563432
[1, 2, 3, ['barry', 'alex']] 44564112
[1, 222, 3, ['barry', 'alex']] 44563432
[1, 2, 3, ['barry', 'alex']] 44564112
[1, 222, 3, ['wusir', 'alex']] 44563312
[1, 2, 3, ['wusir', 'alex']] 44563312

Process finished with exit code 0

深拷贝

import copy
l1 = [1,2,3,['barry','alex']]
l2 = copy.deepcopy(l1)

print(l1,id(l1))  # [1, 2, 3, ['barry', 'alex']] 2915377167816
print(l2,id(l2))  # [1, 2, 3, ['barry', 'alex']] 2915377167048

l1[1] = 222
print(l1,id(l1))  # [1, 222, 3, ['barry', 'alex']] 2915377167816
print(l2,id(l2))  # [1, 2, 3, ['barry', 'alex']] 2915377167048

l1[3][0] = 'wusir'
print(l1,id(l1[3]))  # [1, 222, 3, ['wusir', 'alex']] 2915377167240
print(l2,id(l2[3]))  # [1, 2, 3, ['barry', 'alex']] 2915377167304

E:\python\python_sdk\python.exe E:/python/py_pro/demo.py
[1, 2, 3, ['barry', 'alex']] 59473712
[1, 2, 3, ['barry', 'alex']] 59548256
[1, 222, 3, ['barry', 'alex']] 59473712
[1, 2, 3, ['barry', 'alex']] 59548256
[1, 222, 3, ['wusir', 'alex']] 59473472
[1, 2, 3, ['barry', 'alex']] 59548216

Process finished with exit code 0