Fast Zone Discrimination

This paper describes an algorithm (Fast Zone Discrimination FZD) for analysing Concrete Euler diagrams and listing all present zones. One application area of Euler/Spider diagrams, is modelling failure modes in electronic circuits. For this a procedure is required to check Spider diagrams for logical consistency by ensuring that all present zones in a model have been considered. Unused zones could be viewed as un-handled failure conditions. In order to know which zones have not been used, a complete list of present zones is required for each concrete diagram drawn. To determine if zones are present, a concrete diagram must be examined using programmatic area operations. These area operations are costly of computer time and it is desirable to eliminate all that are unnecessary. The algorithm initially builds two sets of relationships from a concrete diagram and then uses these to target searches for zones that may be present. Using the two sets of relationships eliminates checking for a large number of missing zones; thus processing diagrams quickly and efficiently.