On Fri, Dec 14, 2012 at 1:34 AM, Alexander Korotkov <aekorot...@gmail.com>wrote:
> On Mon, Dec 3, 2012 at 4:31 PM, Alexander Korotkov > <aekorot...@gmail.com>wrote: > >> Actually, I generally dislike path matrix for same reasons. But: >> 1) Output graphs could contain trigrams which are completely useless for >> search. For example, for regex /(abcdefgh)*ijk/ we need only "ijk" trigram >> while graph would contain much more.Path matrix is a method to get rid of >> all of them. >> 2) If we use color trigrams then we need some criteria for which color >> trigrams to expand into trigrams. Simultaneously, we shouldn't allow path >> from initial state to the final by unexpanded trigrams. It seems much >> harder to do with graph than with matrix. >> > > Now, I have an idea about doing some not comprehensive but simple and fast > simplification of graph. I'm doing experiments now. In case of success we > could get rid of path matrix. > Attached patch have following changes: 1) Postphone expansion of colors. Graph are building on color trigrams. 2) Selective expansion of color trigrams into simple trigrams. All non-expanded color trigrams are removed. Such removal leads to union of all states pairs connected with corresponding arcs. Surely, this must no lead to union of initial and final states: that could do all previous work senseless. ------ With best regards, Alexander Korotkov.
trgm-regexp-0.8.patch.gz
Description: GNU Zip compressed data
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