A System for Measuring Function Points from Specifications

We propose a knowledge based approach for the automated measurement of the Function Point metric starting from the specifications of a software system expressed in the form of an Entity Relationship (ER) diagram plus a Data Flow Diagram (DFD). We consider an integration of the two diagrams, which we call ER-DFD, in which the data stores of DFD are substituted by the entities and relationships of the ER. We have specialized the general rules for counting Function Points for the case of a specification in the form of an ER-DFD model. The informal counting rule expressed in natural language have been translated into formal rules that express properties of the ER-DFD graph. A knowledge based system has been implemented in Prolog that automatically counts Function Point by analyzing the graph.