Re: [boost] Re: Re: Re: [review] hash functions

From: Chris Jefferson (caj_at_[hidden])
Date: 2005-03-10 11:30:47

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Thorsten Ottosen wrote:

| so basically you're saying that any collision is much worse than a slower
| hash function because we must use == to go through the bucket ?
|

I would say that if you are designing your own hash function for your
general use, then you can do whatever you find most convient, and try to
optimise.

In general you never want to risk having too many hash collisions (or
even worse, having everything hashing to the same thing), espically for
just a constant time speed increase, as suddenly all your operations can
go from being mostly O(1) (on average) to mostly O(n).. and you know
someone is going to trigger that (in particular, I've made hash tables
of strings where they mostly don't different at the start, while doing
genetic evolution..)

Chris
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