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decimal precision

 
Nijeesh Balan
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Hello All,
I have a simple requirement. I just want to maintain two digits after the decimal point (they should not be rounded off).
for eg., if the value is
i/p -> 3333.8967 ; o/p -> 3333.89
i/p -> 23.8; o/p -> 23.80
i/p -> 4.982 ; o/p -> 4.98
which is the best way to accomplish this?
 
Wayne L Johnson
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One approach is to multiply the value by 100, convert to integer (or long), then divide by 100.0 and assign back to float/double.
For example:
double dval = 3333.8967;
int ival = (int)(dval * 100);
dval = ival / 100.0;
There is still the danger of a round-off occuring. After multiplying the above by 100 you would get 333389. However after dividing by 100.0 you might end up with 3333.8899999999999 instead of 3333.89.
If you only care about DISPLAYING two digits, look at using the "java.text.DecimalFormat" class where you can specify exactly how a real number should be displayed.
 
Nijeesh Balan
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Thanks for the reply..
I tried using DecimalFormat("#.00")
it rounds off as well..
any other suggestions?
 
Wayne L Johnson
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I think if you use the first method I suggested (multiply by 100.0, assign to an int or long, then divide by 100.0), and then print the new value out as a DecimalFormat that you won't get the rounding.

[ September 17, 2003: Message edited by: Wayne L Johnson ]
 
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