Image blur 2. Can't get it to work.

image_blur_2.rb

# Image Blur 1

class Image
  
  def initialize(array)
    @array = array
  end

  def output_image
    @array.each do |row|
      puts row.join(" ")
    end
    nil
  end

  def blur
    @copy = @array
    @array.each.with_index do |row, row_index|
      row.each.with_index do |pixel, col_index|
        if pixel == 1
          @copy.transform(row_index, col_index)
        end
      end
    end
    return @copy
  end

  def transform(row_index, col_index)
    @array[row_index - 1][col_index] = 1
    @array[row_index + 1][col_index] = 1
    @array[row_index][col_index - 1] = 1
    @array[row_index][col_index + 1] = 1
  end

end
# ------------------------------------------------------------------tests
image = Image.new([
  [0, 0, 0, 0],
  [0, 1, 0, 0],
  [0, 0, 0, 1],
  [0, 0, 0, 0]
])

image.blur
image.output_image

Couple of notes. I learned this the hard way, but by setting @copy = @array, you're linking the two together such that changes on one are made to the other. So when you do @array[row_index][col_index + 1] = 1, the program hangs. In order to create the copy such that it is separate from the initial array, you can do the following: @array.each { |row| @copy << row.dup }. Also, for testing purposes, I'd ditch the transform method and include it in the blur method, since they're both a part of achieving the same task, however that's just my opinion and up to you :). Lastly, don't forget to check for edge cases. If you're at col_index of [0] and you do [col_index - 1], that equals to @array[row_index][-1]. [-1] is a way to access the last index of the array, so even though you're at index 0, changing values at [-1] will in this case, change the value of the 3rd index of your column. So if you had [1, 0, 0, 0] at the top row and set if pixel == 1, @array[row_index][col_index - 1] = 1, the top row would then look like this: [1, 0, 0, 1]. This issue also applies to row_index, and also check for issues when you're at the last index in each column or row, and you want to access [+1] of that index (which won't exist). Hope that helps m8 good luck coding.