Published: 2008-07-02
ISBN: 978-91-7519-823-1
ISSN: 1650-3686 (print), 1650-3740 (online)
This paper investigates a novel approach to a type system for modular systems of equations; i.e.; equation systems constructed by composition of individual equation system fragments. The purpose of the type system is to ensure; to the extent possible; that the composed system is solvable. The central idea is to attribute a structural type to equation system fragments that reflects which variables occur in which equations. In many instances; this allows over- and underdetermined system fragments to be identified separately; without first having to assemble all fragments into a complete system of equations. The setting of the paper is equation-based; non-causal modelling; specifically Functional Hybrid Modelling (FHM). However; the central ideas are not tied to FHM; but should be applicable to equation-based modelling languages in general; like Modelica; as well as to applications featuring modular systems of equations outside the field of modelling and simulation.
Equation-based; non-causal modelling; Modelica; Functional Hybrid Modelling; structural analysis; types; type-based analysis; dependent types
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