DIRECTORY CONTENTS: The TimeGraph II temporal reasoning system This directory contains the latest distribution in a tarred, compressed (by gzip) version. TimeGraph II (TG-II) is an efficient system for reasoning about qualitative temporal information. TG-II handles the set of the relations of the Point Algebra and of the Pointizable Interval Algebra. Temporal relations are represented through a "timegraph", a graph partitioned into a collection of "time chains" which are automatically structured for efficiency. The system is scalable, in the sense that the storage tends to remain linear in the number of relations asserted. Efficient query handling is achieved through a time point numbering scheme and a "metagraph" data structure. TG-II is written in Common Lisp. This is a release of TimeGraph-II version 1.0. It has been tested under Allegro Common Lisp 4.2 and Lucid Common Lisp 4.0.0 on Sun SPARC machines running 4.1.3 . The syntax for installing and loading the defsystem outlined in timegraph-II.doc is given for Allegro Common Lisp. We maintain the discussion list bug-tg2@cs.rochester.edu for bug reports and patch announcements. To be put on the bug-tg2@cs.rochester.edu mailing list, send your request to bug-tg2-request@cs.rochester.edu. You are free to use, copy and distribute this software provided that: 1. You report *ALL* bugs to bug-tg2@cs.rochester.edu whether or not you need them fixed. Include the version number (1.0) in the message. 2. You report *ALL* bugs that you fixed to bug-tg2@cs.rochester.edu. Include the version number (1.0) in the message. 3. Every time you run TimeGraph-II on a machine or using a Lisp compiler not mentioned above, you send a message stating the new environment and the version number (1.0) to bug-tg2@cs.rochester.edu 4. You inform us that you obtained a copy of TimeGraph-II by sending a message to bug-tg2-request@cs.rochester.edu. Refer to the file "COPYRIGHT.TEXT" for more details. tg-ii-1.tar.gz contains the following files: README: this file COPYRIGHT.TEXT: the copyright notice COPYING: GNU General Public License definitions.lisp: data structures and global variables of the engine ui-defs.lisp: data structures and global variables of the user interface cl-lib-definitions.lisp: cl-lib macros used by TimeGraph-II timegraph-II.lisp: defsystem tg2.lisp: TimeGraph-II code interval-interface.lisp: interface for entering and querying interval relations point-interface.lisp: interface for entering and querying point relations pointizable-relations: list of pointizable interval algebra timegraph-II.doc: documentation for TimeGraph-II example-interval-relations: an example for specifying interval relations example-point-relations: an example for specifying point relations For a description of the theory underlying the system see: "Efficient Temporal Reasoning through Timegraphs", Alfonso Gerevini and Lenhart Schubert, in Proceedings of IJCAI-93; "Temporal Reasoning in Timegraph I-II", Alfonso Gerevini and Lenhart Schubert, SIGART Bulletin 4(3), 1993. "Efficient Algorithms for Qualitative Reasoning about Time", Alfonso Gerevini and Lenhart Schubert, Artificial Intelligece, to appear; currently available as IRST Technical Report 9307-44, IRST 38050 Povo, TN Italy; or Technical Report 496, Computer Science Department, University of Rochester, 14627 Rochester, USA. FUTURE VERSION -------------- A new version of TimeGraph-II which includes an algorithm for managing disjunctions of point relations is in preparation. This extension will allow the representation of a larger class of interval relations, including in particular disjointness relations such as "interval I before or after interval J".