A wealth of reusable software for solving recur- 

 ring mathematical and statistical problems is 

 already emerging. Unfortunately, the volume of 

 this software and its distribution over 

 labyrinthine computer networks has made it 

 quite difficult for the average user to locate 

 appropriate tools. 



The Guide to Available Mathematical Software 

 (GAMS) is a centralized software resource 

 maintained for scientists at the National Institute 

 of Standards and Technology (NIST). GAMS 

 functions like a management and retrieval sys- 

 tem for a large central software repository. 

 However, instead of maintaining the cataloged 

 software itself, it provides a seamless cross- 

 index to multiple repositories managed by oth- 

 ers. The term virtual software repository has 

 been used to describe systems of this type. 



The steadily increasing collection of software 

 indexed by GAMS now numbers more than 

 9,200 software modules in about 60 mathemati- 

 cal and statistical software packages available 

 from four physically-distributed software reposi- 

 tories, including the well-known netlib collec- 

 tion of public-domain research software main- 

 tained jointly by Oak Ridge National 

 Laboratory, AT&T Bell Laboratories, and the 

 University of Tennessee at Knoxville. Users 

 access GAMS anonymously by logging in to a 

 server system on the Internet. Searches based 

 upon problem classification, keyword, or name 

 may be used to locate appropriate software, after 

 which items such as abstracts, documentation, 

 examples and source code can be retrieved. 

 Both generic and networked (XI 1) graphical 



user interfaces to GAMS have been developed. 



The classification-based retrieval technology 

 used in GAMS is not unique to mathematics and 

 statistics. The system itself can be easily recon- 

 figured to foster the reuse of software in any 

 application field. 



Future directions for the GAMS system include 

 support of the system as a public Internet 

 resource, development of networked GAMS 

 clients and servers, development of improved 

 classification schemes, and research in alternate 

 search mechanisms, including domain-depen- 

 dent expert system methodologies. 



GAMS is a component of an experimental soft- 

 ware exchange being coordinated for the HPCC 

 by the NASA Goddard Space Flight Center. The 

 experiment facilitates the development and eval- 

 uation of multiple approaches to the problem of 

 software reuse in pursuit of an open non-propri- 

 etary architecture to facilitate the emergence of a 

 national software exchange. 



SPONSORING AGENCIES AND 

 ORGANIZATIONS 



NASA 

 NIST 



PERFORMING ORGANIZATIONS 

 AT&T Bell Laboratories 

 NASA 

 NIST 



Oak Ridge National Library 

 University of Tennessee - Knoxville 



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