----------------------------------- Delta Thu Jul 01, 2004 1:43 pm Rounding Decimal Numbers? ----------------------------------- How do you round to decimal places? for example how do I round 8.49999999 to 8.5 Please explain. Thank you. ----------------------------------- Paul Thu Jul 01, 2004 2:16 pm ----------------------------------- isn't it Math.round? like System.out.println(x + " is approximately " + Math.round(x)); ----------------------------------- Tony Thu Jul 01, 2004 2:53 pm ----------------------------------- no, Math.round would round to an integer. What you do is you multiply it by 10^number of decimal places, round, and then divide back. such as 8.499 *10^1 84.99 ~ round 85 /10^1 8.5 ----------------------------------- Delta Thu Jul 01, 2004 3:28 pm ----------------------------------- That's the thing tony... I asked how to round... ----------------------------------- Tony Thu Jul 01, 2004 3:30 pm ----------------------------------- i donno... you can typecast it to an (int) :lol: ----------------------------------- wtd Thu Jul 01, 2004 4:13 pm ----------------------------------- Do you just need this for formatting text? ----------------------------------- zylum Fri Jul 02, 2004 1:10 pm ----------------------------------- no, Math.round would round to an integer. What you do is you multiply it by 10^number of decimal places, round, and then divide back. such as 8.499 *10^1 84.99 ~ round 85 /10^1 8.5 i think tony's way is the only way to do it unless there is some weird function i havent heard of... double num = 8.4999; num *= 10; num = Math.round(num); num /= 10; // or just num = Math.round(num * 10) / 10; System.out.println(num); // gets you 8.5 ----------------------------------- Dan Fri Jul 02, 2004 2:12 pm ----------------------------------- Thats how i do it also. Alougth u whould think there whould be a method for it some where in one of thous java APIs. ----------------------------------- LiquidDragon Fri Jul 09, 2004 7:26 pm ----------------------------------- I always thought there was a round method. But i may be wrong :roll: ----------------------------------- zylum Fri Jul 09, 2004 11:42 pm ----------------------------------- there is a round method but it rounds to the nearest one not the nearest tenth. ----------------------------------- Delta Sat Jul 24, 2004 8:13 am ----------------------------------- Ok well I found some nice lil rounding methods... (I believe this was just for rounding so I could display the text) import java.text.*; DecimalFormat decF = new DecimalFormat ("###.##"); System.out.println (decF (99999.999999)); also decF.setMinimumFractionDigits(2); would set the format to a minimum of two decimal places decF.setMaximumFractionDigits(2); would set the format to a maximum of two decimal places The decimal format thing is only for text as far as I know (for outting it)... but when it came to storing the value I usually ended up using 'long' instead of 'int' or 'double'... because long would actually round how I wanted it to... never the less... thanks for the help.... Have a nice day.