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Array.slice() Method with Example in Ruby
Ruby Array.slice() Method: Here, we are going to learn about the Array.slice() method with examples in Ruby programming language.
Submitted by Hrithik Chandra Prasad, on February 09, 2020
Array.slice() Method
In this article, we will study about Array.slice() method. You all must be thinking the method must be doing something which is related to the slicing of elements or objects in the Array instance. It is not as simple as it looks. Well, we will figure this out in the rest of our content. We will try to understand it with the help of syntax and demonstrating program codes.
Method description:
This method is a public instance method and defined for the Array class in Ruby's library. This method works on element reference and returns the element at the index which is passed with the method invocation. If you are passing two parameters with the method and those parameters are the start and the length then the method will return a subarray which will contain the elements from the start index and till the length index. This method will return subarray in the case when the range is passed as the parameter at the time of method invocation. This method is one of the examples of the non-destructive method where the method does not bring any change in the actual arrangement of objects in the self Array.
Syntax:
array_instance.slice(index) -> object or nil
or
array_instance.slice(start,length)-> new_array or nil
or
array_instance.slice(range)-> new_array or nil
Argument(s) required:
You can provide a single index or range or start and length as the argument inside this method at the time of method call. You will get the output on the basis of the argument you pass inside the method.
Example 1:
=begin
Ruby program to demonstrate slice method
=end
# array declaration
table = [2,4,6,8,10,12,14,16,18,20]
puts "Array slice implementation"
puts "Enter the index you want to slice"
ind = gets.chomp.to_i
if(table.slice(ind))
puts "The element which is sliced is #{table.slice(ind)}"
else
puts "Array index out of bound"
end
puts "Array instance after slicing: #{table}"
Output
Array slice implementation
Enter the index you want to slice
4
The element which is sliced is 10
Array instance after slicing: [2, 4, 6, 8, 10, 12, 14, 16, 18, 20]
Explanation:
In the above code, you can observe that we are slicing the element from the Array instance with the help of Array.slice() method. We are slicing it with the help of an index for which we have asked the user to an input value. The 4th index object has been sliced from the Array instance. The method is not bringing changes in the self Array due to the fact that this method is one of the examples of non-destructive methods.
Example 2:
=begin
Ruby program to demonstrate slice method
=end
# array declaration
table = [2,4,6,8,10,12,14,16,18,20]
puts "Array slice implementation"
puts "Enter the start index you want to slice"
ind = gets.chomp.to_i
puts "Enter the length"
len = gets.chomp.to_i
if(table.slice(ind,len))
puts "The sub array which is sliced is #{table.slice(ind,len)}"
else
puts "Array index out of bound"
end
puts "Array instance after slicing: #{table}"
Output
Array slice implementation
Enter the start index you want to slice
3
Enter the length
5
The sub array which is sliced is [8, 10, 12, 14, 16]
Array instance after slicing: [2, 4, 6, 8, 10, 12, 14, 16, 18, 20]
Explanation:
In the above code, you can observe that we are creating a subarray from the elements of the Array instance with the help of Array.slice() method. We are slicing it with the help of two parameters which namely start index and length for which we have asked the user to input values. In the output, you can see that the Array instance has been sliced from the 3rd index and to the 7th index resulting in the formation of an Array which contains five objects. The method is not bringing changes in the self Array due to the fact that this method is one of the examples of the non-destructive methods.