Catalogue of Artificial Intelligence Techniques
Aliases: Bottom-up, Data-driven Control, Forward Chaining
Categories: Problem Solving
Author(s): P.M.D. Gray
A technique for interpretation or evaluation of a set of clauses which represent constraints or equations on unknown data items. The evaluation proceeds in pseudo-parallel Breadth-first Search fashion starting with those predicates where enough data items have values. These compute values which are then used in other clauses which are added to a queue for evaluation. Evaluation proceeds until no more predicates can be evaluated. Evaluation of some predicates may generate other clauses, in which case care must be taken to avoid an explosion of partially evaluated clauses. Control depends not on the initial order of the clauses, but on the order in which data items get their value. Demons can be used to implement data-directed control.
- Elcock, E.W., McGregor, J.J. and Murray, A.M., Data directed control and operating systems The Computer Journal 15 (1972) no.2, 125-129.