How do I convert a DOUBLE datatype to a two decimal number

[JavaP100]

Hi All,

I have a method that retrieves data from the database. The "Price" column (one of the column it returns) returns a DOUBLE data type. Which means the number could have three numbers AFTER the decimal point. I only want the UI to show a number of a max of TWO decimal points,

Is there some type of NumberFormat API i can use to truncate the third number or "round" up to two decimal points? I read through the NumberFormat Java API and it wasnt clear on how to do this.

Thx

 

[acent]

Take a look at the DecimalFormat class.

Hope this helps.

"If you say you can, or you say you can't, you're right!"
-- Henry Ford

 

[Diancecht]

A double can have much more than three decimals.

Anyway, if you want to do it the simple way:

double myThreeDecimalsDouble = 1.234;
double myTwoDecimalsDouble = Math.round(myThreeDecimalsDouble*100)/(double)100.00;

Cheers,
Dian

 

[sedj]

or :

double d = 111.123456;

double d2 = (int)((d * 100)) / 100.0;

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[Diancecht]

That would truncate it, not round

Cheers,
Dian

 

[sedj]

It will, but the OP says a trunc was fine

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[Diancecht]

But what he actually wants is to round it, trust me. Maybe he still doesn't know it, but that's the truth

Cheers,
Dian

 

[JavaP100]

Thx for the input. I tried this code sugguested above.
-----------------------------------------------------
double myThreeDecimalsDouble = 1.234;
double myTwoDecimalsDouble = Math.round(myThreeDecimalsDouble*100)/(double)100.00;
----------------------------------------------------

it works fine. But problem is that if the Double is 1234.702 (for example) it still displays as 1234.7. i.e it drops the zero. I would want it to still display as 1234.70

Any ideas?

 

[Diancecht]

Oh, I see, then you should use the DecimalFormat class as sugested above:

http://java.sun.com/docs/books/tutorial/java/data/decimalFormat.html

Cheers,
Dian

 

[sedj]

double d = 111.70321321;
DecimalFormat df = new DecimalFormat("###0.00");
System.out.println(df.format(d));

--------------------------------------------------
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http://www.primrose.org.uk

 

[JavaP100]

Hello,

Thx again.

The problem with the code below is that format() returns only a String. I need the value in a double data type. When i try to cast into Double(using Double.parseDouble().

It throws no error but it trunates the zero i.e 1234.70 becomes 1234.7

Is there a work around?

-----------------------------------------------
double d = 111.70321321;
DecimalFormat df = new DecimalFormat("###0.00");
System.out.println(df.format(d));

--------------------------------------------

 

[Diancecht]

Humm.

A double is a value, so 1234.7 is the same as 1234.70.

If you want to display it, use the String. If you want to store it, use double. If you just want to store it with a concrete precision, don't worry about trailing zeros

Cheers,
Dian

 

[sedj]

My answer is the same as Dian's - if you want a double - then use a double - if you want a string to display then use my code !


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[JavaP100]

That helps!!

Thanks a great deal!