2 Decimal Places (that's all)

Question

My output from my calculations is:
2.74594
1.343434343434
14.4758395065893849
How can I limit my digits after the decimal point to only 2 places?
Above answers would be:
2.74
1.34
14.47
Would appreciate any help.

Answer 1

Well your code does exactly what you say it will ;-)
It truncates the number to just 2 places.
But if you want to get the "standard" behaviour of ROUND_HALF_UP then you should use Math.round(), as can be seen in the following.for (int i = 0; i < 100; i++) {
  double d = 2.74594 * i;
  double d2 = d;
  double d3 = d;
  //this code truncates to 2 decimal places
  d2 = d > 0 ? Math.floor(d * 100) / 100.0 : Math.ceil(d * 100) / 100.0;
  d3 = Math.round(d * 100) / 100.0;
  System.out.println("d = " + d + "\td2 = " + d2 + "\td3 = " + d3);
}I usually leave doubles at their default precision until I need to presist or present them(to a db for instance), and then I use a class along the following lines...class Formatter {
  public static final int DEFAULT_PRECISION = 2;
  public static final String DEFAULT_PATTERN = "#.00";
  public static final String ZEROS = "0000000000000000";
  public static String convertDoubleToString(Double d) {
    return convertDoubleToString(round(d, DEFAULT_PRECISION), DEFAULT_PATTERN);
  public static String convertDoubleToString(double d) {
    return convertDoubleToString(round(d, DEFAULT_PRECISION), DEFAULT_PATTERN);
  public static String convertDoubleToString(Double d, int precision) {
    return convertDoubleToString(round(d, precision), "#." + ZEROS.substring(precision));
  public static String convertDoubleToString(double d, int precision) {
    return convertDoubleToString(round(d, precision), "#." + ZEROS.substring(precision));
  public static String convertDoubleToString(Double d, String pattern) {
    return new DecimalFormat(pattern).format(d.doubleValue());
  public static String convertDoubleToString(double d, String pattern) {
    return new DecimalFormat(pattern).format(d);
  private static final double round(Double d, int precision) {
    double factor = Math.pow(10, precision);
    return Math.round((d.doubleValue() * factor)) / factor;
  private static final double round(double d, int precision) {
    double factor = Math.pow(10, precision);
    return Math.round((d * factor)) / factor;
}