find the median of all keys in a map in ruby

One way to find the median of all keys in a map in Ruby is to extract the keys into an array, sort the array, and then calculate the median.

Here is an example implementation:

main.rb
def median_of_map_keys(map)
  keys_array = map.keys.sort
  length = keys_array.length
  median_index = length / 2

  # If the array has an odd number of elements, return the middle element
  if length % 2 == 1
    return keys_array[median_index]
  # If the array has an even number of elements, return the average of the middle two
  else
    return (keys_array[median_index - 1] + keys_array[median_index]) / 2.0
  end
end
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This method takes a map as an argument, converts its keys into an array, sorts the array, and calculates the median. In the case of an odd number of keys, the median is simply the middle element of the sorted array. If there are an even number of keys, the median is the average of the middle two elements of the sorted array.

Here's an example usage:

main.rb
my_map = {2 => "two", 1 => "one", 4 => "four", 3 => "three"}
median_of_map_keys(my_map) #=> 2.5
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In this example, the keys of my_map are 2, 1, 4, 3 and their median is 2.5.