Set common operations in python

Similar to other languages, python set is a disordered, non-repeating element set. its basic functions include link testing and deduplication. the set object also supports the union, intersection, difference, and sysmmetricdifference mathematical operations. python's set is similar to other languages, is an unordered, non-repeating element set. its basic functions include link testing and deduplication. the set object also supports mathematical operations such as union, intersection, difference, and sysmmetric difference.

Sets support x in set, len (set), and for x in set. As an unordered set, sets do not record element positions or insertion points. Therefore, sets do not support indexing, slicing, or sequence-like operations.

Here are a few examples to illustrate

Common operations 1

In [2]: a = set()  In [3]: aOut[3]: set() In [4]: type(a)Out[4]: set In [5]: b = set([1, 3]) In [6]: bOut[6]: {1, 3} In [7]: type(b)Out[7]: set In [8]: b.update(2)---------------------------------------------------------------------------TypeError                 Traceback (most recent call last)
 
   in 
  
   ()----> 1 b.update(2) TypeError: 'int' object is not iterable In [9]: b.update({2}) In [10]: bOut[10]: {1, 2, 3} In [11]: b.update([4]) In [12]: bOut[12]: {1, 2, 3, 4} In [13]: a.dia.difference     a.difference_update a.discard In [13]: a.difa.difference     a.difference_update In [13]: a.difference(b)Out[13]: set() In [14]: aOut[14]: set() In [15]: b.difference(a)Out[15]: {1, 2, 3, 4} In [16]:
  
 

Common operations 2

In [16]: a.add({1, 3})---------------------------------------------------------------------------TypeError                 Traceback (most recent call last)
 
   in 
  
   ()----> 1 a.add({1, 3}) TypeError: unhashable type: 'set' In [17]: a.add(4) In [18]: aOut[18]: {4} In [19]: a.issua.issubset  a.issuperset In [19]: a.issubset(b)Out[19]: True In [20]: a.remove(4) In [21]: aOut[21]: set() In [22]: a.union(b)Out[22]: {1, 2, 3, 4} In [23]: aOut[23]: set() In [24]: bOut[24]: {1, 2, 3, 4} In [25]: b.pop()Out[25]: 1 In [26]: a.copy(b)---------------------------------------------------------------------------TypeError                 Traceback (most recent call last)
   
     in 
    
     ()----> 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]: cOut[29]: set() In [30]: aOut[30]: set() In [31]: a.add({234})---------------------------------------------------------------------------TypeError                 Traceback (most recent call last)
     
       in 
      
       ()----> 1 a.add({234}) TypeError: unhashable type: 'set' In [32]: a.add(234) In [33]: cOut[33]: set() In [34]: aOut[34]: {234}
      
     
    
   
  
 

Common operations 3

In [35]: a.clear() In [36]: aOut[36]: set() In [39]: a = {1} In [40]: b = {1, 2} In [41]: a.intersection(b)Out[41]: {1} In [43]: aOut[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 & bOut[46]: {1} In [47]: a ^ bOut[47]: {2, 3} In [48]: a - bOut[48]: set() In [49]: b - aOut[49]: {2, 3}In [50]: a > bOut[50]: False In [51]: b > aOut[51]: True In [52]: a == bOut[52]: False In [53]: a != bOut[53]: True

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