An interval component for continuous constraints

Local consistency techniques for numerical constraints over interval domains combine interval arithmetic, constraint inversion and bisection to reduce variable domains. In this paper, we study the problem of integrating any specific interval arithmetic library in constraint solvers. For this purpose, we design an interface between consistency algorithms and arithmetic. The interface has a two-level architecture: functional interval arithmetic at low-level, which is only a specification to be implemented by specific libraries, and a set of operations required by solvers, such as relational interval arithmetic or bisection primitives. This work leads to the implementation of an interval component by means of C++ generic programming methods. The overhead resulting from generic programming is discussed.