Re: Patricia trie vs binary search.

From:
Lew <noone@lewscanon.com>
Newsgroups:
comp.lang.java.programmer
Date:
Mon, 28 May 2012 21:54:39 -0700
Message-ID:
<jq1kpt$1ee$1@news.albasani.net>
On 05/28/2012 09:20 AM, Gene Wirchenko wrote:

On Sun, 27 May 2012 22:00:14 -0700, Daniel Pitts
<newsgroup.nospam@virtualinfinity.net> wrote:

On 5/27/12 6:44 PM, Gene Wirchenko wrote:

On Sat, 26 May 2012 17:30:17 -0700, Daniel Pitts
<newsgroup.nospam@virtualinfinity.net> wrote:

[snip]

I tend to use a Deterministic Finite State Automata for this. You can
load the entire English dictionary fairly easily with that scheme. Yes,

        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

you use a bit of memory, but unless you're doing this on an embedded
device, its probably not enough memory to be concerned about.


       Including all affixes?

I suppose it depends on the particular dictionary, but we're only
talking a few hundred thousand entries, at least with the Moby
word-lists as a base:


      Considering how many affixes can be applied to some words, I find
that very questionable:
           self:
                *ish
                *ishly
                un*ish
                un*ishly
                *less
                *lessly
                un*less
                un*lessly
           position:
                *s
                *ed
                *al
                *ally
                re*
                re*s
                re*ed
                *less
                mis*
                *er
                *ers
           friend
                *s
                *ly
                *liness
                be*
                be*ing
                be*ed
                be*er
                be*ers
These are not particularly extreme examples.


It's not a question of how extreme the examples are but how many there are.

Not all words can be legitimately affixed. Many can be affixed by algorithm,
or by bitmaps as to which affixes apply, so you only store the root, the
bitmap and perhaps one more form.

I don't know how much memory expansion you think your factors will cause, as
you only hand wave and say there will be some and act like it's a problem, but
let's say it doubles the size of the dictionary. By Daniel's experiment
upthread, that would bring it to around 8 MiB, let's round and say 10MiB.
Being text and all, that should compress to about 3 MiB or less.

Now I am interested to hear what sort of trouble you assert that 3 MiB or so
of storage will cause.

--
Lew
Honi soit qui mal y pense.
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