Using hash functions with Bloom filters

Posted by dangerstat on Stack Overflow See other posts from Stack Overflow or by dangerstat
Published on 2010-05-02T12:41:37Z Indexed on 2010/05/02 12:47 UTC
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hash

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hashing

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bloom-filter

Hi,

A bloom filter uses a hash function (or many) to generate a value between 0 and m given an input string X. My question is how to you use a hash function to generate a value in this way, for example an MD5 hash is typically represented by a 32 length hex string, how would I use an MD5 hashing algorithm to generate a value between 0 and m where I can specify m? I'm using Java at the moment so an example of to do this with the MessageDigest functionality it offers would be great, though just a generic description of how to do about it would be fine too.

Thanks

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