浅谈python中set使用_Python

浅谈python中set使用

2020-08-30 10:21Python教程网 Python

下面小编就为大家带来一篇浅谈python中set使用。小编觉得挺不错的，现在就分享给大家，也给大家做个参考。一起跟随小编过来看看吧

浅谈python中set使用

									In [2]: a = set()  # 常用操作1 

									In [3]: a 

									Out[3]: set() 

									In [4]: type(a) 

									Out[4]: set

									In [5]: b = set([1, 3]) 

									In [6]: b 

									Out[6]: {1, 3} 

									In [7]: type(b) 

									Out[7]: set

									In [8]: b.update(2) 

									---------------------------------------------------------------------------

									TypeError                 Traceback (most recent call last) 

									<ipython-input-8-d51e2fe4c50a> in <module>() 

									----> 1 b.update(2) 

									TypeError: 'int' object is not iterable 

									In [9]: b.update({2}) 

									In [10]: b 

									Out[10]: {1, 2, 3} 

									In [11]: b.update([4]) 

									In [12]: b 

									Out[12]: {1, 2, 3, 4} 

									In [13]: a.di 

									a.difference     a.difference_update a.discard 

									In [13]: a.dif 

									a.difference     a.difference_update 

									In [13]: a.difference(b) 

									Out[13]: set() 

									In [14]: a 

									Out[14]: set() 

									In [15]: b.difference(a) 

									Out[15]: {1, 2, 3, 4} 

									In [16]:

常用操作2

									In [16]: a.add({1, 3}) 

									---------------------------------------------------------------------------

									TypeError                 Traceback (most recent call last) 

									<ipython-input-16-98cdf4d0875e> in <module>() 

									----> 1 a.add({1, 3}) 

									TypeError: unhashable type: 'set'

									In [17]: a.add(4) 

									In [18]: a 

									Out[18]: {4} 

									In [19]: a.issu 

									a.issubset  a.issuperset 

									In [19]: a.issubset(b) 

									Out[19]: True

									In [20]: a.remove(4) 

									In [21]: a 

									Out[21]: set() 

									In [22]: a.union(b) 

									Out[22]: {1, 2, 3, 4} 

									In [23]: a 

									Out[23]: set() 

									In [24]: b 

									Out[24]: {1, 2, 3, 4} 

									In [25]: b.pop() 

									Out[25]: 1

									In [26]: a.copy(b) 

									---------------------------------------------------------------------------

									TypeError                 Traceback (most recent call last) 

									<ipython-input-26-9e8a5f057ffd> in <module>() 

									----> 1 a.copy(b) 

									TypeError: copy() takes no arguments (1 given) 

									In [27]: a.copy() 

									Out[27]: set() 

									In [28]: c = a.copy() 

									In [29]: c 

									Out[29]: set() 

									In [30]: a 

									Out[30]: set() 

									In [31]: a.add({234}) 

									---------------------------------------------------------------------------

									TypeError                 Traceback (most recent call last) 

									<ipython-input-31-6073e02d68a9> in <module>() 

									----> 1 a.add({234}) 

									TypeError: unhashable type: 'set'

									In [32]: a.add(234) 

									In [33]: c 

									Out[33]: set() 

									In [34]: a 

									Out[34]: {234}

常用操作3

									In [35]: a.clear() 

									In [36]: a 

									Out[36]: set() 

									In [39]: a = {1} 

									In [40]: b = {1, 2} 

									In [41]: a.intersection(b) 

									Out[41]: {1} 

									In [43]: a 

									Out[43]: {1} 

									In [44]: b = {1, 2, 3} 

									In [45]: a.union(b) 

									Out[45]: {1, 2, 3} 

									In [45]: a.union(b) 

									Out[45]: {1, 2, 3} 

									In [46]: a & b 

									Out[46]: {1} 

									In [47]: a ^ b 

									Out[47]: {2, 3} 

									In [48]: a - b 

									Out[48]: set() 

									In [49]: b - a 

									Out[49]: {2, 3}<BR><BR> 

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									11 In [50]: a > b 

									Out[50]: False

									In [51]: b > a 

									Out[51]: True

									In [52]: a == b 

									Out[52]: False

									In [53]: a != b 

									Out[53]: True