Ubuntu Manpage: clips - an expert system programming language

NAME

       clips     - an expert system programming language

SYNOPSIS

       clips [ file.clp ]

DESCRIPTION

       CLIPS  is  a productive development and delivery expert system tool which provides a complete environment
       for the construction of rule and/or object based expert systems.  CLIPS is being used by  numerous  users
       throughout  the  public  and  private  community  including: all NASA sites and branches of the military,
       numerous federal bureaus, government contractors, universities, and many companies.  The key features  of
       CLIPS are:

       Knowledge Representation
              CLIPS  provides  a  cohesive  tool for handling a wide variety of knowledge with support for three
              different  programming  paradigms:  rule-based,   object-oriented   and   procedural.   Rule-based
              programming allows knowledge to be represented as heuristics, or "rules of thumb," which specify a
              set  of  actions to be performed for a given situation. Object-oriented programming allows complex
              systems to be modeled as modular components (which can be easily reused to model other systems  or
              to  create  new components). The procedural programming capabilities provided by CLIPS are similar
              to capabilities found in languages such as C, Pascal, Ada, and LISP.

       Portability
              CLIPS is written in C for portability and speed and has been installed on many different computers
              without code changes. Computers on which CLIPS has been tested include an IBM PC running  DOS  and
              Windows 95 and a Macintosh running MacOS and Mach.  CLIPS can be ported to any system which has an
              ANSI  compliant C compiler.  CLIPS comes with all source code which can be modified or tailored to
              meet a user's specific needs.

       Integration/Extensibility
              CLIPS can be embedded within  procedural  code,  called  as  a  subroutine,  and  integrated  with
              languages  such  as C, FORTRAN and ADA.  CLIPS can be easily extended by a user through the use of
              several well-defined protocols.

       Interactive Development
              The standard version of CLIPS provides an  interactive,  text  oriented  development  environment,
              including  debugging  aids,  on-line help, and an integrated editor. Interfaces providing features
              such as pulldown menus, integrated editors, and multiple  windows  have  been  developed  for  the
              Macintosh, Windows 95, and X Window environments.

       Verification/Validation

              CLIPS  includes  a number of features to support the verification and validation of expert systems
              including support for modular design and partitioning of a  knowledge  base,  static  and  dynamic
              constraint  checking of slot values and function arguments, and semantic analysis of rule patterns
              to determine if inconsistencies could prevent a rule from firing or generate an error.

       Fully Documented
              CLIPS comes with extensive documentation including a a User's Guide, a Basic Programming Guide, an
              Advanced Programming Guide and an Architecture Manual. All of these documents are provided in  the
              Debian clips-doc package.

BUGS

       CLIPS is old software so bugs are not unheard of.

HISTORY

The origins of the C Language Integrated Production System (CLIPS) date back to 1984 at NASA's Johnson
Space Center. At this time, the Artificial Intelligence Section (later the Software Technology Branch,
Client/Server Systems Branch, and now the Information Technology Office) had developed over a dozen
prototype expert systems applications using state-of-the-art hardware and software. However, despite
extensive demonstrations of the potential of expert systems, few of these applications were put into
regular use. This failure to provide expert systems technology within NASA's operational computing
constraints could largely be traced to the use of LISP as the base language for nearly all expert system
software tools at that time. In particular, three problems hindered the use of LISP based expert system
tools within NASA: the low availability of LISP on a wide variety of conventional computers, the high
cost of state-of-the-art LISP tools and hardware, and the poor integration of LISP with other languages
(making embedded applications difficult).

The Artificial Intelligence Section felt that the use of a conventional language, such as C, would
eliminate most of these problems, and initially looked to the expert system tool vendors to provide an
expert system tool written using a conventional language. Although a number of tool vendors started
converting their tools to run in C, the cost of each tool was still very high, most were restricted to a
small variety of computers, and the projected availability times were discouraging. To meet all of its
needs in a timely and cost effective manner, it became evident that the Artificial Intelligence Section
would have to develop its own C based expert system tool.

The prototype version of CLIPS was developed in the spring of 1985 in a little over two months.
Particular attention was given to making the tool compatible with expert systems under development at
that time by the Artificial Intelligence Section. Thus, the syntax of CLIPS was made to very closely
resemble the syntax of a subset of the ART expert system tool developed by Inference Corporation.
Although originally modelled from ART, CLIPS was developed entirely without assistance from Inference or
access to the ART source code.

The original intent for CLIPS was to gain useful insight and knowledge about the construction of expert
system tools and to lay the groundwork for the construction of a replacement tool for the commercial
tools currently being used. Version 1.0 demonstrated the feasibility of the project concept. After
additional development, it became apparent that CLIPS would be a low cost expert system tool ideal for
the purposes of training. Another year of development and internal use went into CLIPS improving its
portability, performance, functionality, and supporting documentation. Version 3.0 of CLIPS was made
available to groups outside of NASA in the summer of 1986.

Further enhancements transformed CLIPS from a training tool into a tool useful for the development and
delivery of expert systems as well. Versions 4.0 and 4.1 of CLIPS, released respectively in the summer
and fall of 1987, featured greatly improved performance, external language integration, and delivery
capabilities. Version 4.2 of CLIPS, released in the summer of 1988, was a complete rewrite of

CLIPS for code modularity. Also included with this release were an architecture manual providing a
detailed description of the CLIPS software architecture and a utility program for aiding in the
verification and validation of rule-based programs. Version 4.3 of CLIPS, released in the summer of 1989,
added still more functionality.

Originally, the primary representation methodology in CLIPS was a forward chaining rule language based on
the Rete algorithm (hence the Production System part of the CLIPS acronym). Version 5.0 of CLIPS,
released in the spring of 1991, introduced two new programming paradigms: procedural programming (as
found in languages such as C and Ada;) and object-oriented programming (as found in languages such as the
Common Lisp Object System and Smalltalk). The object-oriented programming language provided within CLIPS
is called the CLIPS Object-Oriented Language (COOL). Version 5.1 of CLIPS, released in the fall of 1991,
was primarily a software maintenance upgrade required to support the newly developed and/or enhanced X
Window, MS-DOS, and Macintosh interfaces. Version 6.0, released in the Spring of 1993, added fully
integrated object/rule pattern matching and support features for rule-based software engineering. Version
6.1, released in the Summer of 1998, added C++ compatibility and functions for profiling performance.

Because of its portability, extensibility, capabilities, and low-cost, CLIPS has received widespread
acceptance throughout the government, industry, and academia. The development of CLIPS has helped to
improve the ability to deliver expert system technology throughout the public and private sectors for a
wide range of applications and diverse computing environments. CLIPS is being used by over 5,000 users
throughout the public and private community including: all NASA sites and branches of the military,
numerous federal bureaus, government contractors, universities, and many private companies.

CLIPS is now maintained as public domain software by the main program authors who no longer work for
NASA.

Derivative works for CLIPS have also appeared, such as:

JESS The Java Expert System Shell, which provides a CLIPS interpreter for the Java programming
language.

fuzzyCLIPS
A fuzzy extension of CLIPS.

bw CLIPS A version of CLIPS using backward chains.

AUTHOR

       As  with  any  large  project,  CLIPS  is  the  result  of  the  efforts  of numerous people. The primary
       contributors have been: Robert Savely, previous branch chief of  the  STB  and  now  chief  scientist  of
       advanced  software  technology  at  JSC,  who  conceived  the  project and provided overall direction and
       support; Chris Culbert, current chief of the Information Technology  Office,  who  managed  the  project,
       wrote  the  original  CLIPS  Reference Manual, and designed the original version of CRSV; Gary Riley, who
       designed and developed the rule-based portion of

       CLIPS , coauthored the CLIPS Reference Manual and CLIPS Architecture Manual, and developed the  Macintosh
       interface  for  CLIPS  ;  Brian  Donnell,  who  designed and developed the CLIPS Object Oriented Language
       (COOL), coauthored the CLIPS Reference Manual and CLIPS Architecture Manual, and developed  the  previous
       MS-DOS  interfaces  for CLIPS ; Bebe Ly, who was responsible for maintenance and enhancements to CRSV and
       is now responsible for developing the X Window interface  for  CLIPS;  Chris  Ortiz,  who  developed  the
       Windows 3.1 interface for CLIPS; Dr. Joseph Giarratano of the University of Houston-Clear Lake, who wrote
       the CLIPS User's Guide; and Frank Lopez, who designed and developed CLIPS version 1.0 and wrote the CLIPS
       1.0 User's Guide.

       Many  other  individuals  contributed  to  the design, development, review, and general support of CLIPS,
       including: Jack Aldridge, Carla Armstrong, Paul Baffes, Ann Baker, Stephen Baudendistel, Les  Berke,  Tom
       Blinn,  Marlon  Boarnet,  Dan  Bochsler, Bob Brown, Barry Cameron, Tim Cleghorn, Major Paul Condit, Major
       Steve Cross, Andy Cunningham, Dan Danley, Mark Engelberg, Kirt Fields, Ken Freeman, Kevin Greiner,  Ervin
       Grice,  Sharon  Hecht,  Patti  Herrick,  Mark  Hoffman,  Grace Hua, Gordon Johnson, Phillip Johnston, Sam
       Juliano, Ed Lineberry, Bowen Loftin, Linda Martin, Daniel McCoy, Terry  McGregor,  Becky  McGuire,  Scott
       Meadows,  C. J. Melebeck, Paul Mitchell, Steve Mueller, Bill Paseman, Cynthia Rathjen, Eric Raymond, Reza
       Razavipour, Marsha Renals, Monica Rua, Tim Saito, Gregg Swietek, Eric Taylor, James Villarreal, Lui Wang,
       Bob Way, Jim Wescott, Charlie Wheeler, and Wes White.

COPYRIGHT

       This  manpage  was  made  by Javier Fernández-Sanguino <jfs@debian.org> for Debian GNU/Linux  (but may be
       used by others)

Linux                                               July 2003                                           CLIPS(1)