Computation algorithms and optimal procedures for digital terrain model production = Algoritmi di calcolo e procedure ottimali per la produzione di modelli digitali del terreno

Various strategies have been proposed for the construction of a digital terrain model (DTM), the availability of which is a necessary requirement for the development of a Geographic Information System. This paper deals with a method of DTM generation, which has been applied to a large data set. Its procedures are based on approximation theory, finite elements theory and least square collocation. Computation problems arise for DTM generation by least square collocation from large data sets; in these cases linear algebra routines for the solution of large sparse system have been used. Special emphasis is given to the stages, where human interface is required.