How to I disply only 3 numbers after dot of double?

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barakmitz
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How to I disply only 3 numbers after dot of double?

Post by barakmitz » Sat Nov 22, 2008 12:12 pm

Hi,
I want to sidply Double variables but I want it always to be 3 numbers after the dot
Example:
4 ---> 4.000
1642.63787565 ----> 1642.638

and so on
how can i do this?
I heard something about printf but im not sure how to use it or if it works...

Thanks

mf
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Re: How to I disply only 3 numbers after dot of double?

Post by mf » Sat Nov 22, 2008 1:04 pm

System.out.printf("%.3f\n", Math.PI);

cjrr2046
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Re: How to I disply only 3 numbers after dot of double?

Post by cjrr2046 » Sun Dec 28, 2008 9:08 pm

double a1=2.02356323; // Any double //
DecimalFormat df=new DecimalFormat ("0.000");
String a2=df.format (a1);
System.out.println (a2);

DecimalFormat is in this package: java.text.DecimalFormat;

jpaul
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Joined: Sat May 02, 2009 6:28 am

To format a double...

Post by jpaul » Sat May 02, 2009 6:42 am

Hi!
You can use DecimalFormat for create someone format for the floating point numbers, as double, but you don't need that... You should use the next form for print data, I test that is the faster form for print data in Java.

Code: Select all

PrintWriter out = new PrintWriter(new OutputStreamWriter(System.out));
// use for all output

out.printf("%.3f\n", Math.PI);

// use to endish
out.flush();

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