confusion in double operations...

[Vishal K Patel]

double d = 18.99 + 1.80;
System.out.println(d);

o/p : 20.79

double d = 18.99 + 1.90;
System.out.println(d);

o/p : 20.889999999999997

i think in 2nd case o/p should be 20.89...!!!
and actually i want the o/p 20.89.
what could be done..?

help me out...

[Chandra Bhatt]

Hi,

Use printf():

System.out.printf("%.2f",d);

or you can use:

 
java.util.NumberFormat nf = java.util.NumberFormat.getInstance();
nf.setMaximumFractionDigits(2);
double d1=233.231232;
System.out.println(nf.format(d1));

Thanks,
[ May 30, 2007: Message edited by: Chandra Bhatt ]

[Prasad Tamirisa]

This is ok....But why is it happening so??

I mean,

why is it not 2.89 in 2nd case?
and why is it different in fist case?

[Prasad Tamirisa]

Can any one take a look at this?
Please.

[Barry Gaunt]

Originally posted by Prasad Tamirisa:
Can any one take a look at this?
Please.

Tried Google for "floating point arithmetic accuracy" or similar? You will find discussions of floating point arithmetic accuracy in an elementary numerical mathematics course book.

[Prasad Tamirisa]

Wow....! Thats a great reference.

Thanks once again barry. You have been so helpful to me these days.

[Barry Gaunt]

Originally posted by Prasad Tamirisa:
Wow....! Thats a great reference.

Thanks once again barry. You have been so helpful to me these days.

Yes, I like to help people with initiative