Exploring Summation and Product Operators in the Refinement Calculus

A syntactic calculation of Morgan's least conjunctive refinement operator for predicate transformers is developed. The operator is used to develop a general approach to lifting relational operators to predicate transformer operators. Predicate ...

ILP systems which use some form of Inverse Entailment (IE) are based on clause refinement through a hypotheses space bounded by a most specific clause. In this paper we give a new analysis of refinement operators in this setting. In particular, Progol'...

Refinement operators for triangular meshes as used in subdivision schemes or remeshing are discussed. A numbering scheme is presented, covering all refinement operators that (topologically) map vertices onto vertices. Using this characterization, some ...