Printing large double values without the exponential notation? - Java

[b4ukiran]

Hi all,

I have a requirement to print large double values without the exponential notaion. The double value can be a declared variable or any calculated value within the code. In any case, I should be able to print the result without containing the exponential notation. Please help me out.

[JosAH]

Have a look at the DecimalFormat class; it can do the job.

kind regards,

Jos

[b4ukiran]

Hi,

I tried to use the java.text.DecimalFormat class in the following sample code:

[code]
import java.text.DecimalFormat;

public class prog2
{
public static void main(String args[])
{
String str = "1234567890123456789000.1234567890";
Double d = new Double(str);
double dd = d.doubleValue();
dd = dd + 123.0;
DecimalFormat formatter = new DecimalFormat("##0.0######");
System.out.println(formatter.format(dd));
}
}
[code]

I got the o/p as: 1234567890123456800000.0. Any more suggestions on this...

[JosAH]

Hi,

I tried to use the java.text.DecimalFormat class in the following sample code:

import java.text.DecimalFormat;
 
public class prog2
{
public static void main(String args[])
{
String str = "1234567890123456789000.1234567890";
Double d = new Double(str);
double dd = d.doubleValue();
dd = dd + 123.0;
DecimalFormat formatter = new DecimalFormat("##0.0######");
System.out.println(formatter.format(dd));
}
}
 

I got the o/p as: 1234567890123456800000.0. Any more suggestions on this...

A double number can only store +- 15 significant digits (with a decimal dot somewhere,
that's why it's called a 'floating point number'). Your example contains way too
many significant digits, i.e. they can't all be stored in a double. The number, say,
1.23e45 would've been fine (less than 15 significant digits).

If you want numbers like that you need the BigDecimal class.

kind regards,

Jos

ps. In the Java Articles section there's an 'index' article containing a link to the
paper "What every computer scientist should know about floating point arithmetic".
It's a must read.

[dbush3721]

Hi all,

I have a requirement to print large double values without the exponential notaion. The double value can be a declared variable or any calculated value within the code. In any case, I should be able to print the result without containing the exponential notation. Please help me out.

double d = 0.0000005;
System.out.println(new DecimalFormat("#.#######################").format( d));