CUTE - CONSTRAINED AND UNCONSTRAINED TESTING ENVIRONMENT

The purpose of this article is to discuss the scope and functionality of a versatile environment for testing small- and large-scale nonlinea r optimization algorithms. Although many of these facilities were orig inally produced by the authors in conjunction with the software packag e LANCELOT, we believe that they will be useful in their own right and should be available to researchers for their development of optimizat ion software. The tools can be obtained by anonymous ftp from a number of sources and may, in many cases, be installed automatically. The sc ope of a major collection of test problems written in the standard inp ut format (SIF) used by the LANCELOT software package is described. Re cognizing that most software was not written with the SIF in mind, we provide tools to assist in building an interface between this input fo rmat and other optimization packages. These tools provide a link betwe en the SIF and a number of existing packages, including MINOS and OSL. Additionally, as each problem includes a specific classification that is designed to be useful in identifying particular classes of problem s, facilities are provided to build and manage a database of this info rmation. There is a Unix and C shell bias to many of the descriptions in the article, since, for the sake of simplicity, we do not illustrat e everything in its fullest generality. We trust that the majority of potential users are sufficiently familiar with Unix that these example s will not lead to undue confusion.