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Subject: Re: Repitition detection

Author: Russell Reagan

Date: 02:24:54 12/27/02

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On December 27, 2002 at 04:54:42, Dan Andersson wrote:

>What Bruce is refering to is the idea that if a hash collision happens you
>simply put the offending hash in the next available slot. The possible problem
>is that you get a chaining. I.e. a long sequence of occupied slots. But that is
>rare. I prefer using a recoding algorithm that computes a new index, the net
>result is the same. The hash should be at least twice as large as the depth of
>search to get good behaviour. A mean number of probes less than two. One other
>idea is to create a new hash table each time a capture is made. The question is
>if the extra bookkeeping will make it a win, I'd guess no.

Ok. Makes sense so far. So, when you probe, you start with the "normal" index
that you get from the hash key (key % size, or whatever), and then compare hash
keys until you find a match, or until you hit an entry where the "index" portion
of the keys no longer match? Or do you stop probing at a certain number? For
example, Vincent says he uses 8 probes. Does that mean he starts at the "normal"
index, and iterates until he either gets a hit, or until he has tried 8 slots?

Russell



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