Re: How best to implement a hash table in Mathematica
- To: mathgroup at smc.vnet.net
- Subject: [mg125061] Re: How best to implement a hash table in Mathematica
- From: Joseph Gwinn <joegwinn at comcast.net>
- Date: Mon, 20 Feb 2012 02:47:25 -0500 (EST)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
- References: <jho21j$5sb$1@smc.vnet.net> <jhqmsq$fbt$1@smc.vnet.net>
In article <jhqmsq$fbt$1 at smc.vnet.net>,
Richard Fateman <fateman at cs.berkeley.edu> wrote:
> On 2/18/2012 3:28 AM, Joseph Gwinn wrote:
> > I have an application that resembles dictionary lookup, with significant
> > rates of collision.
> >
> >...
>
> Mathematica presumably already uses hashing for storage of stuff like
>
> f[{a,b,c}] = value1
> f[{1,2,c}] = value2
>
> etc.
>
> Initializing a hashtable with 10^4 (identical?) empty keys makes no
> sense. Did I misunderstand your message?
No, you understood correctly. Please see my response to David Bailey
for the rationale.
Joe Gwinn