1. bit pattern matching
From: "Ricardo M. Forno" <rforno at uyuyuy.com>
Subject: RE: bit manipulation
<<If you are searching for an exact match (lets say 100110010), and you have
it in a character string (a sequence), you migth try this:>>
The matching that I want to do is probably a little unusual.
First I want to align the most significant bits of the two samples.
Then I want to determine the number of bits that match, up to the first
mismatch, but not beyond.
The ratio of the number of matching bits to the length of the primary sample
should be a useful measure of the degree of match.
Juergen Luethje very kindly sent me a proposal to do this which looks very
promising. I am not yet in position to use it.
Allen
2. Re: bit pattern matching
On 26 May 2004, at 23:42, Allen Robnett wrote:
>
>
> From: "Ricardo M. Forno" <rforno at uyuyuy.com>
> Subject: RE: bit manipulation
>
>
> <<If you are searching for an exact match (lets say 100110010), and you have
> it
> in a character string (a sequence), you migth try this:>>
>
> The matching that I want to do is probably a little unusual.
> First I want to align the most significant bits of the two samples.
> Then I want to determine the number of bits that match, up to the first
> mismatch, but not beyond. The ratio of the number of matching bits to the
> length
> of the primary sample should be a useful measure of the degree of match.
Oh, then you want to search email records for DCuny's difference code,
which i asked for some 4 or 5 yrs ago. It's a great starting point for tweaking
to your specific application of this sort. It works as he submitted it to the
email list, but never made it to the user contribs page, afaik. I looked for it
here for an hour, since i did significant tweaking, speed tests, and
verification
tests for data loss, but i'm afraid since no one was interested back then,
that's some of the code i deleted.
Look up similarity.e by R. M. Forno too.
Kat
3. Re: bit pattern matching
On 27 May 2004, at 2:18, Kat wrote:
>
>
> On 26 May 2004, at 23:42, Allen Robnett wrote:
>
> >
> > From: "Ricardo M. Forno" <rforno at uyuyuy.com>
> > Subject: RE: bit manipulation
> >
> >
> > <<If you are searching for an exact match (lets say 100110010), and you have
> > it in a character string (a sequence), you migth try this:>>
> >
> > The matching that I want to do is probably a little unusual.
> > First I want to align the most significant bits of the two samples.
> > Then I want to determine the number of bits that match, up to the first
> > mismatch, but not beyond. The ratio of the number of matching bits to the
> > length of the primary sample should be a useful measure of the degree of
> > match.
>
> Oh, then you want to search email records for DCuny's difference code,
> which i asked for some 4 or 5 yrs ago. It's a great starting point for
> tweaking
> to your specific application of this sort. It works as he submitted it to the
> email list, but never made it to the user contribs page, afaik. I looked for
> it
> here for an hour, since i did significant tweaking, speed tests, and
> verification tests for data loss, but i'm afraid since no one was interested
> back then, that's some of the code i deleted.
Tiggr had a copy squirreled away, being a kat, i found it anyhow. You want
wrdcomp.e by David Cuny. There's lapses in the comparisons for nested
inequalities, which i'll call "features", in it's operation. Fixing them to
locate
*all* possible resync points in nested sentences or databases takes 2x as
much code and way, way more cpu time. You'll want to delete duplicate re-
sync points *before* wasting time re-searching nested differences between
sequences/words. Case sensitivity shouldn't be a problem for your bits tho.
Kat
> Look up similarity.e by R. M. Forno too.
>
> Kat
>
>
>
>
