Shared Tools:  Reference Manual
    Release Level 5.4 Release Date 2008 10 Revision Level 1.0
Last modified on:   Monday, 20-Jul-09 14:05 CEST

RTXPS:  forward chaining RULES

The forward chaingin RULES are very similar to the first order production rules used in the backward chaining version of the expert system, XPS.

The main difference is the ACTION or consequence part: while in the backward chaining branch, this is always an ASSIGNMENT setting the value of a DESCRIPTOR, the forward chaining system uses a repertoir of ACTIONS so that the general rule syntax looks like:

    IF [CONDITION]
      AND/OR [CONDITION] (evaluates to TRUE)
    THEN (execute) ACTION
where ACTION can be
  1. an ASSINGMENT of the form:  DESCRIPTOR == VALUE,
  2. any one of the built in FUNCTIONS;
  3. a user defined, named ACTION from the RTXPS ACTION Configuration file.


© Copyright 1995-2016 by:   ESS   Environmental Software and Services GmbH AUSTRIA | print page