Getting numbers after decimal Java

Question

Possible Duplicate:
Strange floating-point behaviour in a Java program
Why does JSP/JSTL division by 1000 sometimes give remainder?

I am trying to get the numbers after the decimal. ex: 60.4 -> 0.4

Yet, when do

double a = 60.4 % 1;

it comes out to be 0.3999999999999986.

Why is this? And how could it be fixed?

Read and digest : http://docs.oracle.com/cd/E19957-01/806-3568/ncg_goldberg.html. Floating point primitives have limited precision in Java — mcfinnigan, May 21 '12 at 09:12
@mcfinnigan or any language - see many duplicates here - but I can't seem to get a good query for tem — mmmmmm, May 21 '12 at 09:17
See also the helpful [floating point info. page](http://stackoverflow.com/tags/floating-point/info) *"Many questions asked here about floating point math are about small inaccuracies in floating point arithmetic. To use the example from the excerpt, `0.1 + 0.1 + 0.1` might result in `0.300000001` instead of the expected `0.3`. Errors like these are caused by the way floating point numbers are represented in computers' memory. .."* — Andrew Thompson, May 21 '12 at 09:20

score 4 · Accepted Answer · answered May 21 '12 at 09:13

4

Use fixed-point types

BigDecimal src = new BigDecimal("60.4");
BigDecimal a = src.remainder(BigDecimal.ONE);

answered May 21 '12 at 09:13

turbanoff

score 1 · Answer 2 · answered May 21 '12 at 09:18

1

You can use DecimalFormat to do your desired task.

answered May 21 '12 at 09:18

SilentBomb

Could you elaborate how? – aioobe May 21 '12 at 09:26
NumberFormat formatter = new DecimalFormat("#0.000"); in constructor you can specified the desired numbers' – SilentBomb May 21 '12 at 09:46

score 0 · Answer 3 · edited May 23 '17 at 12:04

0

I think this is exactly what you are looking for. So essentially you can use:

double x = d - Math.floor(d);

OR

BigDecimal class for exact digits after decimal.

edited May 23 '17 at 12:04

Community

answered May 21 '12 at 09:17

Kuldeep Jain

3 Answers3