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This paper describes features of a language approach for map algebra based on the use of algebraic expressions that satisfy a concise formalism. To be consistent with formal approaches such as geoalgebra and image algebra, the proposed algebraic expressions are suitable not only for the usual modeling of layers but also to describe variable neighborhoods and zones. As a compromise between language and implementation issues we present an implementation strategy based on the theory of automata. The result is an efficient way of implementing map algebra that simplifies its use on environmental and dynamic models without going too far from its well-known paradigm.

Abstract. This work investigates the practical issue of mapping existing GIS to the OpenGIS standards. We describe the data models used in three systems (MGE, ARC/INFO and SPRING) and analyse the problems involved when mapping them to OpenGIS. Our conclusion is that the OpenGIS standard has not been defined in a formal and unequivocal way, and therefore, there are indefinitions and competing alternatives for mapping existing GIS systems into the proposed standard.

This paper introduces a presentation language for GIS. This language is designed to be used a standalone tool, or in conjunction with a query and manipulation functions. The proposed language is based on an objet-oriented data model and on concepts used in the object-oriented query language proposed standard OQL (Object Query Language). The language is part of the SPRING environment, a GIS system which integrates the diverse types of spatial data (cadastral maps, thematic maps, digital terrain models and images).