Convert Double to a ByteArray

I need to convert several values to Byte Arrays so that they can be transmitted in a DataGramPacket. One of these values is a Double. What is the best way to do this? The data contained in the double needs not have a scale greater than 4.
With other values such as Shorts or Longs, I can represent them using a BigInteger and use BigInteger.toByteArray, but am unable to do this with Doubles as I would lose everything after the decimal point.
Thanks in advance

Knowing that a double is a 64 bits value, which means it has the same number of bytes than a "long", you can produce a long value that represents your double
long l = Double.doubleToRawLongBits(d)where d is the double you want to represent as a byte array. And then you can use this new long as an ordinary long number.
To get your double back, just use
double Double.longBitsToDouble(long l)

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I need something like this:
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WOW thanks a lot. These are definately better than what I thought of doing originally.
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Seems like Blue Sky is not clear
You want to convert what into what?
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It's an extremely important skill to learn to read the API and become familiar with the tools you will use to program Java. Java has an extensive set of documentation that you can even download for your convenience. These "javadocs" are indexed and categorized so you can quickly look up any class or method. Take the time to consult this resource whenever you have a question - you'll find they typically contain very detailed descriptions and possibly some code examples.
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Asumming your data is big-endian, you should be able to simply typecast it to a DBL (see attache LV 7.0 example).
(It is possible that your DBL string is little-endian, in this case it will be slightly more complicated. Let us know )Message Edited by altenbach on 05-27-2005 04:49 PM
LabVIEW Champion . Do more with less code and in less time .
Attachments:
StringToDBL.vi ‏23 KB

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This problem only occurs when dealing with large numbers or numbers with a lot of fraction digits.
Here is an example:
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float f1 = (float)d;
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Hi,
I have a requirement to convert the double to a speicfic pattern.
Example:
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output: 000000000122223 -----> total 15 digits
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Awaiting
DARMA

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Thanks.

I am very new to Java Programming, but I am trying to
convert a double to a string
Here is some code of what I am trying to do:
String output = "";
Word words[] = new Word[ 7 ];
Then I add the "words" to the array
for ( int i = 0; i < words.length; i++ ) {
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].listings()) + "\n";
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toString to convert a double to a string but am not
sure how to go about doing it.
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Thanks.Wrong:
Double.toString(words[ i ].listings())
Right:
words[ i ].listings().toString()

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All,
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hi xamule,
tey this..
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int x=d.intValue();
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bye bye,
Pramod

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Convert Double to a ByteArray

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