def alpha_hist(freqs, scale, fg, bg)
      histogram = Image.new(HISTOGRAM_COLS, HISTOGRAM_ROWS) do
        self.background_color = bg
        self.border_color = fg
      end

      gc = Draw.new
      gc.affine(1, 0, 0, -scale, 0, HISTOGRAM_ROWS)
      gc.fill('white')

      HISTOGRAM_COLS.times do |x|
        gc.point(x, freqs[x])
      end

      gc.draw(histogram)
      histogram['Label'] = 'Alpha'

      histogram
    end
def alpha_hist(freqs, scale, fg, bg)
      histogram = Image.new(HISTOGRAM_COLS, HISTOGRAM_ROWS) do
        self.background_color = bg
        self.border_color = fg
      end

      gc = Draw.new
      gc.affine(1, 0, 0, -scale, 0, HISTOGRAM_ROWS)
      gc.fill('white')

      HISTOGRAM_COLS.times do |x|
        gc.point(x, freqs[x])
      end

      gc.draw(histogram)
      histogram['Label'] = 'Alpha'

      histogram
    end
The alpha frequencies are shown as white dots.