oscaruser@programmer.net
2006-Jul-14 00:18 UTC
[Xapian-discuss] xapian uses inverted index?
Folks, Been looking the IR docs [http://www.xapian.org/docs/intro_ir.html], but didn't see anything about an inverted index. Is such a datastructure used by Xapian to help relevancy, improve search results or a method to determine context? e.g., "At a simple level a computerised IR system puts the terms in a direct access, or index file. A term can be looked up and its posting list found." Thanks, OSC -- ___________________________________________________ Play 100s of games for FREE! http://games.mail.com/
On Thu, Jul 13, 2006 at 03:17:34PM -0800, oscaruser@programmer.net wrote:> Been looking the IR docs [http://www.xapian.org/docs/intro_ir.html], > but didn't see anything about an inverted index. Is such a > datastructure used by Xapian to help relevancy, improve search > results or a method to determine context? e.g., "At a simple level a > computerised IR system puts the terms in a direct access, or index > file. A term can be looked up and its posting list found."Inverted indexes can't really help relevancy and similar (at least, I don't see how they can). They're basically a way of quickly figuring out which documents contain which terms efficiently. They're essential to practical implementations of the kind of IR system Xapian provides. Xapian, in some ways, is just some smart algorithms on top of an inverted index. J -- /--------------------------------------------------------------------------\ James Aylett xapian.org james@tartarus.org uncertaintydivision.org