class Helper extends ErrorAware {

    public static String doubleTo15DigitString(double d) {
        // from https://stackoverflow.com/a/8820013/1320237
        // from https://stackoverflow.com/questions/4885254/string-format-to-format-double-in-java#comment5434509_4885329
        return String.format(Locale.US, "%.15f", d);
    }

}