×

Document filtering via directed acyclic graphs

  • US 5,873,081 A
  • Filed: 06/27/1997
  • Issued: 02/16/1999
  • Est. Priority Date: 06/27/1997
  • Status: Expired due to Term
First Claim
Patent Images

1. A method of filtering incoming documents against user queries, comprising the steps of:

  • receiving a plurality of user queries, the queries including terms connected by logical operators;

    embedding the user queries in a directed acyclic graph having a plurality of nodes, each node in the graph including pointers to any successor nodes thereof, the terms in the queries embedded as source nodes in the graph and the operators embedded as internal nodes;

    receiving at least one document;

    evaluating the at least one document against the directed acyclic graph by comparing at least some of the terms in said document with the source nodes in the directed acyclic graph, and for each term that matches a source node, evaluating an internal successor node of the matched source node based on the logical operator represented by the successor node and truth information of the predecessor nodes thereto, to determine a truth value of said internal successor node; and

    returning truth information indicative of which of the successor nodes were evaluated as true.

View all claims
  • 2 Assignments
Timeline View
Assignment View
    ×
    ×