How to format a double without converting it into string type

Question

I want values like

1,
1.0,
0

to be formatted to

1.00,
1.00,
0.00

I'm using the following code,

Double stringToNumber=Double.parseDouble("3");
DecimalFormat toTheFormat = new DecimalFormat("0.00");
toTheFormat.format(stringToNumber)

.format returns a string and if I parse using Double.parseDouble() method.

I lose the precision, i,e 3.00 becomes 3.0 again.How to solve this?

Hi, why would you format Double? It usually task to be done on the UI with the help of formatters. — nomadus, Dec 09 '16 at 04:42
Numbers are values; they don't have a format. They can be converted to strings in a particular format. But the *value* `1.00` is identical to `1.0`. Hence the question doesn't make sense. — shmosel, Dec 09 '16 at 04:46
@nomadus I'm creating and writing a excel in java using jxl jar. Here I want to insert a floating point value without losing the precision. So i'm using Double. — Francis Raj, Dec 09 '16 at 04:52
Which library are you using to download into XLS? Is it Apache POI? — nomadus, Dec 09 '16 at 04:54
something like this.... http://stackoverflow.com/questions/6536405/jxl-number-format-and-cell-type — Vincent, Dec 09 '16 at 05:02

nomadus · Accepted Answer · 2016-12-09T05:03:39.837

0

Would this work? I have made changes

    public class Tester {
    public static void main (String[] args) {
        double d = 1;
        NumberFormat numFormat = NumberFormat.getInstance();
        numFormat.setMaximumFractionDigits(3);
        numFormat.setMinimumFractionDigits(2);
        System.out.println(numFormat.format(d));
    }
}

edited Dec 09 '16 at 05:03

answered Dec 09 '16 at 04:51

nomadus

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This will print 1.346 - fine, but if try to print 1, it should print like 1.00, but this code doesn't do so. Still thanks for the reply. – Francis Raj Dec 09 '16 at 04:56
It now prints 1.00, if the number is 1. – nomadus Dec 09 '16 at 05:04
`numFormat.format(d)` returns a string and i cannot insert number as a string, i can do it, but in excel sheet it would prompt as error. – Francis Raj Dec 09 '16 at 06:25
Yes, I agree. This has to be done in JXL side where you set the format of XLS cell to numeric. – nomadus Dec 09 '16 at 06:35
Could you try this? WritableCellFormat cf2 = new WritableCellFormat(NumberFormats.FLOAT); Number n = new Number(2,1,3.1415926535,cf2); s.addCell(n); – nomadus Dec 09 '16 at 06:43

How to format a double without converting it into string type

1 Answers1