The descriptor theory-what is it about?

摘要

The flowgraph theory of N.E. Fenton and R.W. Whitty (1984) definesnhow to map program structure onto flowgraphs. What is the aim? The goalnthey want to reach is the usage of flowgraphs as a sound basis fornmeasuring certain aspects of complexity. This measurement is, due to thenchosen basis, done in an objective way. The aspects of complexitynmeasured depend on the respective application, i.e. the kinds ofncomplexity needed to get the results demanded by the user. But puttingnthe flowgraph theory described in this paper into practice reveals somenweak points which destroy the general applicability of this theory. Thisnis the reason why we developed a model, which is in fact still based onnthe flowgraph theory but enhanced by so-called descriptors. Thisnenhancement makes it possible to handle programming as well asnspecification languages. As a consequence we are able to measure formalndescriptions of both types in an objective way with the help of the samenconstructs and theories. The work was carried out as part of an ESPRITnII project COSMOS (Cost Management with Metrics of Specification)