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# fixed length decimal numbers

Namnai Kidorkar
Greenhorn
Posts: 25
How do I get fixed length decimal number in java float or double?

say, i've 22 and want to devide it with 7.

i want to get 3.14 not 3.14285.....

help please.

Ulf Dittmer
Rancher
Posts: 42968
73
The java.text.NumberFormat class does this; check out in particular the setMaximumFractionDigits and setMinimumFractionDigits methods.
Of course, then you'll have a string, but you can convert it back easily enough.
[ September 29, 2005: Message edited by: Ulf Dittmer ]

Edwin Keeton
Ranch Hand
Posts: 214
1. Multiply the result times 100.
2. round()
3. Divide by 100

Rick O'Shay
Ranch Hand
Posts: 531
>> I want to get 3.14 not 3.14285

In fact you really don't know what the value is until you observe it. So it makes sense to display it in the form you want while preserving the maximum precision the rest of the time.

double value = 3.143423432432;
System.out.printf("%.2f", value); // Prints: 3.14

Layne Lund
Ranch Hand
Posts: 3061
As Rick points out, you should make a distinction between how the number is stored and how it is displayed. When doing calculations, you should store the value as precisely as possible. However, when you display it, you can use either NumberFormat or, if you can use Java 5.0 features, PrintStream.printf() for the exact formatting you want.

Layne

Naveen Vooka
Greenhorn
Posts: 25
Another alternate to round a double value, make a java.text.DecimalFormat like:
static DecimalFormat df=new DecimalFormat("0.00");
use
System.out.println(df.format(aDoubleValue));
and it does the rounding.

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Naveen Vooka
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