-*- mode:Text -*-
Copyright 1992 Patrick H. Winston.  All rights reserved.
Version 1.1.1, transferred from master disk on 23 Apr 93
 
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PURPOSE

Provides program support program support for Chapter 12, Symbolic
Constraints and Propagation.
Illustrates constraint propagation using time intervals.

PERFORMANCE EXPERIMENT 1

Examine the file time.exp.  Run the search experiments by
typing the following command to your lisp system:

(load "time.exp")

Alternatively, evaluate each Lisp expression in the file one at a
time, noting what each does.

PERFORMANCE EXPERIMENT 2

Run the time constraint-propagation procedure with other time
nets.

SMALL-SCALE LISP PROJECT

Delete the propagation steps in the procedure that establishes
surviving labels.  Then implement a mechanism that does
propagation by applying the label-constraining procedure to all
node triples.

MEDIUM-SCALE LISP PROJECT

Implement a mechanism for propagating time constraints along
reference nodes.