Ruby Ranges

Ruby range represents a set of values with a beginning and an end. They can be constructed using s..e and s…e literals or with ::new.

The ranges which has .. in them, run from beginning to end inclusively. The ranges which has … in them, run exclusively the end value.

puts (-5..-1).to_a       

puts (-5...-1).to_a       

puts ('a'..'e').to_a      

puts ('a'...'e').to_a

Output:

Ruby has a variety of ways to define ranges.

• Ranges as sequences
• Ranges as conditions
• Ranges as intervals

---

Ranges as Sequences

The most natural way to define a range is in sequence. They have a start point and an end point. They are created using either .. or … operators.

We are taking a sample range from 0 to 5. The following operations are performed on this range.

Example:

#!/usr/bin/ruby   



  



range = 0..5   



  



puts range.include?(3)   



ans = range.min   



puts "Minimum value is #{ans}"   



  



ans = range.max   



puts "Maximum value is #{ans}"   



  



ans = range.reject {|i| i < 5 }   



puts "Rejected values are #{ans}"   



  



range.each do |digit|   



   puts "In Loop #{digit}"   



end  

Output:

---

Ranges as Conditions

Ranges are also defined as conditional expressions. Different conditions are defined in a set of lines. These conditions are enclosed within start statement and end statement.

Example:

#!/usr/bin/ruby   



budget = 50000   



  



watch = case budget   



   when 100..1000 then "Local"   



   when 1000..10000 then "Titan"   



   when 5000..30000 then "Fossil"   



   when 30000..100000 then "Rolex"   



   else "No stock"   



end   



  



puts watch

Output:

---

Ranges as Intervals

Ranges can also be defined in terms of intervals. Intervals are represented by === case equality operator.

Example:

#!/usr/bin/ruby   

if (('a'..'z') === 'v')   

  puts "v lies in the above range"   

end   

  

if (('50'..'90') === 99)   

  puts "z lies in the above range"   

end

Output:

---

Ruby Reverse Range

Ruby reverse range operator does not return any value. If left side value is larger than right side value in a range, no vlaue will be returned.

Example:

#!/usr/bin/ruby   



    puts (5..1).to_a  

Nothing will be returned in the output for the above example.

To print a reverse order, you can use reverse method in a normal range as shown below.

Example:

#!/usr/bin/ruby   

    puts (1..5).to_a.reverse

Output: