class MoreMath::Sequence

def geometric_mean
  sum = @elements.inject(0.0) { |s, t|
    case
    when t > 0
      s + Math.log(t)
    when t == 0
      break :null
    else
      break nil
    end
  }
  case sum
  when :null
    0.0
  when Float
    Math.exp(sum / size)
  else
    0 / 0.0
  end
end