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From Yonik Seeley <ysee...@gmail.com>
Subject Float.floatToRawIntBits
Date Wed, 16 Nov 2005 20:21:22 GMT
Float.floatToRawIntBits (in Java1.4) gives the raw float bits without
normalization (like *(int*)&floatvar would in C).  Since it doesn't do
normalization of NaN values, it's faster (and hopefully optimized to a
simple inline machine instruction by the JVM).

On my Pentium4, using floatToRawIntBits is over 5 times as fast as
floatToIntBits.
That can really add up in something like Similarity.floatToByte() for
encoding norms, especially if used as a way to compress an array of
float during query time as suggested by Doug.

-Yonik
Now hiring -- http://forms.cnet.com/slink?231706

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