Precision with float

i wana know how to display the value
5.1234
as
5.12
i wana know which package/class to use.
i checked with lang.Math and Math classes but i culd not understand which to use.
can somebody help me in this.
thanx

Hi
You can do the following:
String num = "5.1234";
//BigDecimal is A class in java.math
BigDecimal bDec = new BigDecimal(num);
//setScale sets the number of digits after the Decimal Point
// The Second argument tells the program whether to igonore the
// remaining digits or round them.
//See the API documentation for more information on these
bDec = bDec.setScale(2, BigDecimal.ROUND_UP);
//This should print out 5.12
System.out.println(bDec.toString());
Good Luck!
Eshwar Rao
Developer Technical Support
Sun microsystems inc
http://www.sun.com/developers/support

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Precision with float and double values

Hi, does anyone knows how can i get more precise calculations with floating point numbers? Let's see an example:
public class Teste {
public static void main(String args[]) {
float i = 0;
while (i<=10) {
System.out.println(i);
i=i+0.1f;
/* output
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.70000005
0.8000001
0.9000001
1.0000001
1.1000001
1.2000002
1.3000002
1.4000002
1.5000002
1.6000003
1.7000003
1.8000003
1.9000003
2.0000002
2.1000001
2.2
2.3
2.3999999
2.4999998
2.5999997
2.6999996
2.7999995
2.8999994
2.9999993
3.0999992
3.199999
3.299999
3.399999
3.4999988
3.5999987
3.6999986
3.7999985
3.8999984
3.9999983
4.0999985
4.1999984
4.2999983
4.399998
4.499998
4.599998
4.699998
4.799998
4.8999977
4.9999976
5.0999975
5.1999974
5.2999973
5.399997
5.499997
5.599997
5.699997
5.799997
5.8999968
5.9999967
6.0999966
6.1999965
6.2999964
6.3999963
6.499996
6.599996
6.699996
6.799996
6.899996
6.9999957
7.0999956
7.1999955
7.2999954
7.3999953
7.499995
7.599995
7.699995
7.799995
7.899995
7.9999948
8.099995
8.199995
8.299995
8.399996
8.499996
8.599997
8.699997
8.799997
8.899998
8.999998
9.099998
9.199999
9.299999
9.4
9.5
9.6
9.700001
9.800001
9.900002
*/

http://forum.java.sun.com/thread.jsp?forum=31&thread=357174

Draw fct with float

Does someone know why all draw fonction like drawArc, drawLine use int instead of float or double? it would not be more precise to draw with float or double?
thx

fonction? LOL!
Seriously though, the method you want is java.awt.Graphics2D.draw(Shape) and fill(Shape). You would use it like this:
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Excuse my english, thanks in advance,
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Thank you for your report. And I have found the root cause.
In BaseCompose.as
protected function composeFloat(elem:InlineGraphicElement, afterLine:Boolean):Boolean
if (!floatFits && (_curParcel.fitAny || _curParcel.fitsInHeight(totalDepth, int(logicalFloatHeight))) && (!_curLine || _curLine.absoluteStart == floatPosition || afterLine))
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The condition of if is true, only when the weird behavior happens. We need to discuss about how to fix it.

Problem with Float - round down error

I have to save in database (MySql) amount which is passed by user. For instance user writes 99999999999. But Float.parseFloat(request.getParameter("amoUnit")) returns value 9.9999998E10 . When I save this value in database I receive 99999998000.00. I want to have in database exactly what the user has written. Should I use differen data type? Thanks in advance.

leonkaP wrote:
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Smart Forms : problem with Float Variable

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Hi,
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Draw line with float values possible

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not possible
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JSlider with Floating point values

I desperatly need to create a JSlider with floating/decimal values. For example between 0 and 1 and ticks within an interval of 0.1.
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How to creat N number of pulses precisely with PCTIO-10

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http://digital.ni.com/public.nsf/3efedde4322fef19862567740067f3cc/48a4924ba92f431c8625686900773e96?OpenDocument

Converting Vector with Floats to float[] typecast error?

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Hi,
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>
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Problem with floating point precision

Hello!
I need to store in a variable a number like this 1234512345.123412345.
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If you are going to use the BigDecimal class, it is worth bearing in mind a tip that was passed on to me from georgemc. If you create the BigDecimal class instances using the constructor that accepts a String as input, then you can easily specify how many digits should follow the decimal point.

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Dear Experts....
For my application I have to perform demodulation operation on FPGA. I want to store an array of double precision number. When I am trying to perform any double precision number operation I am getting this error "Wire:Type not supported in current target" From forums I came to know that on FPGA in Labview 2011 I cannot have double precision operation. What is alternative?? Please help me with this. Due to this issue my work has been delayed due to this problem..
Thanks... Kindly guide...
Solved!
Go to Solution.

Dear Mathan, thanks for your reply.... I have already gone throught the link you sent, but for my application I have to have array of floating points number. I can not have integer numbers. Here I have attached my vi. I have to mix a signal of 20 Mhz with sin and cos signal to achieve demodulation. So for Sin and Cos values I have to have floating point. Is ther any way to overcome this problem?
Attachments:
fpga.vi ‏30 KB

Precision with float

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