python sets documentation code example

Example 1: insert python3

a = [1,2,3,4,5]

#a.insert(index_to_insert_at, num_to_insert)
a.insert(0, -1)

# a is now: [-1,1,2,3,4,5]

Example 2: python set &

>>> A = {0, 2, 4, 6, 8};
>>> B = {1, 2, 3, 4, 5};

>>> print("Union :", A | B)  
Union : {0, 1, 2, 3, 4, 5, 6, 8}

>>> print("Intersection :", A & B)
Intersection : {2, 4}

>>> print("Difference :", A - B)
Difference : {0, 8, 6}

# elements not present both sets
>>> print("Symmetric difference :", A ^ B)   
Symmetric difference : {0, 1, 3, 5, 6, 8}

Example 3: set except python

# Program to perform different set operations 
# as we do in  mathematics 
  
# sets are define 
A = {0, 2, 4, 6, 8}; 
B = {1, 2, 3, 4, 5}; 
  
# union 
print("Union :", A | B) 
  
# intersection 
print("Intersection :", A & B) 
  
# difference 
print("Difference :", A - B) 
  
# symmetric difference 
print("Symmetric difference :", A ^ B)

Example 4: python list comprehension

#example: removing common elements found in `a` from `b`.
a = [1,2,3,4,5]
b = [5,6,7,8,9]
# desired output: [1,2,3,4]

# gets each item found in `a` AND not in `b`
print([i for i in a if i not in b])