Set In Python

Sets 

• Set is unordered collection of Items, unordered means data can be saved randomly at any location, and not the way it was provided

 #program

 s1 = {10, 20, 30, 40, 50, 60, 70, 80, 90}   # what trying to store
 s2 = {9, 80, 7, 60, 5, 40, 3, 20, 1}   # what trying to store
 print("s1 : ", s1)
 print("s2 : ", s2)


 #output

 s1 :  {70, 40, 10, 80, 50, 20, 90, 60, 30}       # how it got stored (unordered)
 s2 :  {1, 3, 5, 7, 40, 9, 80, 20, 60}            # how it got stored (unordered)

• To declare Set, { } (curly brackets) are used.

                         Syntax :
                                Tuple_name = {member1, member2,..}

 #program

 s1 = {10, 20, 30, 40, 50, 60, 70, 80, 90}   # what trying to store
 print("s1       : ", s1)
 print("type(s1) : ", type(s1))


 #output

 s1       :  {70, 40, 10, 80, 50, 20, 90, 60, 30}  # how it got stored (unordered)
 type(s1) :  <class 'set'>

• Duplicates are not allowed.

 #program

 s1 = {10, 20, 30, 40, 50, 40, 30, 20, 10}   # provided repeat items

 print("s1 : ", s1)


 #output

 s1 :  {40, 10, 50, 20, 30}        #duplicates values not stored

• Accessing using indexing is not allowed, hence slice operator can not be used.

 #program

 s1 = {10, 20, 30, 40, 50, 40, 30, 20, 10}   # provided repeat items
 print("s1 : ", s1)
 print("s1[2] : ", s[2])


 #output

 s1 :  {40, 10, 50, 20, 30}
 Traceback (most recent call last):
   File "C:/Self_Practice_Er_M_S_Dandyan/Python/Pycharm/xml/main.py", line 5, in <module>
     print("s1[2] : ", s[2])
 NameError: name 's' is not defined

• Empty Set can not be declares, if do so will become a dictionary.  

 #program

 s1 = {}   # provided repeat items
 print("s1       : ", s1)
 print("type(s1) : ", type(s1))


 #output

 s1       :  {}
 type(s1) :  <class 'dict'>

Set have some Built In Methods