Negative Boolean constraints

Negative Boolean Constraints

Systems of Boolean constraints which allow negative constraints such as f 6 6 g are investigated. The results form a basis for algorithms to determine satissability, validity, implication, equivalence and variable elimination for such systems. These algorithms have applications in spatial query decomposition, machine reasoning, and constraint logic programming. Proofs of the results rely on ind...

Constraints in Non-Boolean Contexts

In high-level constraint modelling languages, constraints can occur in non-Boolean contexts: implicitly, in the form of partial functions, or more explicitly, in the form of constraints on local variables in non-Boolean expressions. Specifications using these facilities are often more succinct. However, these specifications are typically executed on solvers that only support questions of the fo...

Boolean surfaces with shape constraints

In this paper, we present a new method for the construction of parametric surfaces reproducing an object from a set of spatial data. We adopt a hybrid scheme, based on the Boolean sum of variable degree spline operators, which both interpolate a set of grid lines and approximate the data. As usual the variable degrees can be chosen to satisfy proper shape constraints. c © 2007 Elsevier Ltd. All...

From Boolean Equalities to Constraints

Although functional as well as logic languages use equality to discriminate between logically different cases, the operational meaning of equality is different in such languages. Functional languages reduce equational expressions to their Boolean values, True or False, logic languages use unification to check the validity only and fail otherwise. Consequently, the language Curry, which amalgama...

Boolean Constraints for XML Modeling