How to Use the flatten Method in Ruby
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Contents
In this article, you will learn how to use the flatten method in Ruby.
The flatten Method
The flatten method in Ruby is used to convert a multi-dimensional array into a one-dimensional array. This method returns a new array that contains all the elements of the original array and its sub-arrays, in a single dimension.
Here is an example of how to use the flatten method in Ruby:
arr = [1, 2, [3, 4], [5, 6, [7, 8]]]
flatten_arr = arr.flatten
puts flatten_arr.inspect
In the above example, the arr array contains two sub-arrays. The flatten method is used to convert the arr array into a one-dimensional array called flatten_arr. The output of this code will be:
[1, 2, 3, 4, 5, 6, 7, 8]
As you can see, the flatten method has taken all the elements of the original array and its sub-arrays, and combined them into a single array.
The flatten method also accepts an optional argument, which specifies the depth to which the array should be flattened. For example, if you have a multi-dimensional array with nested sub-arrays, you can specify how many levels of nesting you want to flatten. Here is an example:
arr = [1, 2, [3, 4], [5, 6, [7, 8]]]
flatten_arr = arr.flatten(1)
puts flatten_arr.inspect
In this example, the flatten method is called with an argument of 1, which means that only the top-level arrays should be flattened. The output of this code will be:
[1, 2, 3, 4, 5, 6, [7, 8]]
As you can see, the flatten method has only flattened the top-level arrays, and the nested sub-array [7, 8] is still a sub-array in the flattened array.