The set is an unordered collection with no duplicate items. Like other languages, Ruby also provides a set class that represents the mathematical notion of a set. Here, we will discuss the basic set operations, i.e., Union, Intersection, and Difference.
Union
In Ruby, the union takes two objects like arrays, vectors, hashes, etc. as arguments and results in a third object which contains all the elements from both the objects and removes duplicate elements. You can perform a union between two arrays using the pipe operator(|).
Syntax:
x | yParameters: x and y are the sequence items of objects.
For Example:
[1, 2, 1, 2, 3, 5, 7] | [1, 2, 3, 4] #=> [1, 2, 3, 4, 5, 7]
Example 1:
# Ruby program to illustrate the union # Array arr_1 = [ 2 , 4 , 5 , 6 , 7 , 9 , 1 , 2 , 4 ]
arr_2 = [ 2 , 4 , 5 , 6 , 9 , 8 , 0 , 3 , 3 ]
# Union result = arr_1 | arr_2
# Display result
puts "#{result}"
|
Output:
[2, 4, 5, 6, 7, 9, 1, 8, 0, 3]
Example 2:
# Ruby program to illustrate Union of arrays class MultiSet
attr_accessor :set
def initialize(set)
@set = set
end
# Union def |(other)
@set | other.set
end
end x = MultiSet. new ([ 1 , 1 , 2 , 2 , 3 , 4 , 5 , 6 , 7 , 8 ])
y = MultiSet. new ([ 1 , 3 , 5 , 6 , 8 ])
p x | y |
Output:
[1, 2, 3, 4, 5, 6, 7, 8]
Intersection
In Ruby, intersection takes two objects like arrays, vectors, hashes, etc. as arguments and results in a third object which contains elements that are common in both the objects and remove duplicates. The order in the intersection is preserved from the original array. You can perform intersection either by using & operator or by using the intersection() function.
Syntax:
x & yParameters: x and y are the sequence items of objects.
For Example:
[ 'a', 'b', 'b', 'z' ] & [ 'a', 'b', 'c' ,'z'] #=> [ 'a', 'b' ,'z']
Example 1:
# Ruby program to illustrate the intersection method # requires the set require "set"
x = Set. new ([ 1 , 2 , 3 , 4 ])
y = Set. new ([ 1 , 2 , 4 ])
# Intersection method used res = x.intersection(y) # Prints the res puts res |
Output:
Set: {1, 2, 4}
Example 2:
# Ruby program to illustrate intersection of arrays class MultiSet
attr_accessor :set
def initialize(set)
@set = set
end
# Intersection def &(other)
@set & other.set
end
x = MultiSet. new ([ 1 , 1 , 2 , 2 , 3 , 4 , 5 , 6 , 7 , 8 ])
y = MultiSet. new ([ 1 , 3 , 5 , 6 , 8 ])
p x & y end |
Output:
[1, 3, 5, 6, 8]
Difference
In Ruby, difference takes two objects like arrays, vectors, hashes, etc. as arguments and returns the difference of both the objects. You can perform difference either by using – operator or by using the difference() function.
Syntax:
x – yParameters: x and y are the sequence items of objects.
For Example:
[ 22, 45, 89, 76 ] - [ 22, 22, 89, 79 ] #=> [45]
Example 1:
# Ruby program to illustrate the difference method # requires the set require "set"
x = Set. new ([ 1 , 2 , 3 , 4 ])
y = Set. new ([ 1 , 2 , 4 , 5 ])
# Difference method used res = x.difference(y) # Prints the res puts res |
Output:
Set: {3}
Example 2:
# Ruby program to illustrate difference of arrays class MultiSet
attr_accessor :set
def initialize(set)
@set = set
end
# Difference def -(other)
@set - other.set
end
x = MultiSet. new ([ 1 , 1 , 2 , 2 , 3 , 4 , 5 , 6 , 7 , 8 ])
y = MultiSet. new ([ 1 , 3 , 5 , 6 , 8 ])
p x - y end |
Output:
[2, 2, 4, 7]