Key words: Graph Theory, Crisp and Fuzzy Reasoning
Many different types of logical reasoning and logical operations that must be preformed on individual or multiple data planes can be implemented in GIS. Users and creators of the system should fully understand this logical reasoning. Most such logical operations are done outside the software package. Within the framework of this paper, we offer a method based on graph theory, for the implementation of logical reasoning in graphical software packages such as CAD or GIS. We suggest some graph models for different types of logical problems both in crisp and fuzzy cases. Their principles are discussed and some specific problems are solved.