Histogram class written in Ruby. Also a frequency method is added to the Array class.

histogram.rb

class Histogram
  #Create the object
  def initialize(words)
    #These are used later for calculating how many * are displayed
    @highestWordCount = 0
    @longestCharWord = 0
    #Save the original word array
    @raw = words
    @wordsHash = Hash.new
    #place words in hash
    @raw.each do |word|
      #This will be used later for the display method
      if word.length > @longestCharWord
        @longestCharWord = word.length
      end
      #Check if word exists in hash
      if @wordsHash[word].nil?
        @wordsHash[word] = @raw.count(word)
        if @raw.count(word) > @highestWordCount
          @highestWordCount = @raw.count(word)
        end
      end
    end
  end
  #Output histogram
  def display(n = -1)
    #Only display n number of words
    count = 0
    #Calculate how much space the word with the most entries needs to fill
    spaceAvailable = (77 - @longestCharWord).round(2)
    if (spaceAvailable < @highestWordCount)
      scale = (@highestWordCount / spaceAvailable)
      #This sets how the scale is displayed to the user
      displayScale = scale.round(3).to_s()
    else
      scale = (spaceAvailable / @highestWordCount)
      #In this case each * represents less than one word
      displayScale = (@highestWordCount / spaceAvailable).round(3).to_s()
    end
    #Display the scale to the user
    print "Scale: 1 * = " + displayScale + " word(s)\n\n"
    #Sort by value, descending
    sorted = @wordsHash.sort_by {|k,v| v}.reverse
    #Loop through each key, value pair in the hash
    sorted.each do |word, num|
      if count < n || n == -1
        #Number of spaces after word so pipes line up
        spaces = " "*(@longestCharWord - word.length)
        #Check how many stars should be displayed
        if spaceAvailable < num
          numToDisplay = num / scale
        else
          numToDisplay = num*scale
        end
        #Display the string
        print word + spaces + " |" + "*"*(numToDisplay) + "\n"
        count = count + 1
      else
        break
      end
    end
    nil
  end
end


#Bonus points
class Array
  def frequency
    returnHash = Hash.new
    #Loop through each item in the array
    self.each do |item|
      #Check if word exists in hash
      if returnHash[item].nil?
        returnHash[item] = self.count(item)
      end
    end
    returnHash
  end
end

arr = ["bradley", "kyle", "kyle", "bye", "hello", "bye", "bye", "bye", "bye", "bye", "bye", "test", "test", "bradley", "test", "test", "test", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "hello", "bradley", "bradley", "bradley", "bradley", "hello", "hello", "hello", "bradley", "bradley", "hello", "bradley", "hello", "bradley"]

#RUN THE THING!
hs = Histogram.new(arr)
hs.display

#Returns a hash
puts arr.frequency