Float Arrays and hashcodes

Hi,
I have some problems with generating unique hash codes for float arrays.
The following code will result in "true" on my JVM (JRE 1.6):
System.out.println(Arrays.hashCode(new float[]{0,1,2,3,6,9}) == Arrays.hashCode(new float[]{0,1,3,6,8,9}));Does anyone have an idea how to generate a truly unique hashcode for float arrays?
Thanks for your help,
Dieter

JoachimSauer wrote:
dkleinrath wrote:
JoachimSauer wrote:
But again: you don't usually need a perfect hash. Why do you think you need one?I use static HashMaps to store meta information about specific arrays. I also use a HashSet to search for unique arrays in a big collection of arrays.That's ok. Both HashMap and HashSet can work perfectly with in-perfect hash code (obviously, since perfect hash codes are not possible in many situations).
What they can not handle is .equals() being "wrong" (i.e. inconsistent with hashCode()).
This means that you can't directly use float[] as keys.
You could build a simple wrapper around float[] to be used as keys, 'though.I just tried that and it works like a charm.
Thank you very much for your help.

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