convert_to_decimal

# File activesupport/lib/active_support/number_helper/rounding_helper.rb, line 26
        def convert_to_decimal(number)
          case number
          when Float, String
            BigDecimal(number.to_s)
          when Rational
            BigDecimal(number, digit_count(number.to_i) + options[:precision])
          else
            number.to_d
          end
        end