Re: [boost] [Gauge for interest] Minimal perfect hash function generator

From: Matthias Troyer (troyer_at_[hidden])
Date: 2005-01-18 15:10:43

On Jan 17, 2005, at 5:16 PM, Beman Dawes wrote:

> At 04:51 AM 1/17/2005, Matt Hurd wrote:
>
> >Perfect hashing and statistically reasonable hashing are quite
> >different but practically the same ;-)
>
> Isn't that stretching it a bit? Collision handling code can be 
> eliminated if you know the hashing is perfect, for example. Although I 
> do understand your point that for many practical applications, perfect 
> hashing and statistically reasonable hashing would yield very similar 
> performance.
>
> Seems like both could have a place in Boost.
>
> Statistically reasonable hashing of particular sets of strings has 
> been a need that I've often run into.

To me perfect hashing has the big advantage that it vectorizes on 
vector supercomputer, in which case it is not at all comparable to 
statistically reasonable hashing which will always be dominated by 
worst-case performance on vector machines.

Matthias