public static String format(final double value, final int integerDigit, final int fractionDigit) {
		df_extra.setMaximumFractionDigits(fractionDigit);
		df_extra.setMinimumFractionDigits(fractionDigit);

		df_extra.setMinimumIntegerDigits(integerDigit);
		return df_extra.format(value);
	}