@hackage AERN-Basics2011.1

foundational type classes for approximating exact real numbers

Type-classes abstracting various kinds of approximations for exact entities:

  • those that are near to the exact value due to limited granularity (eg floating point numbers with fixed granularity (aka precision) approximating real numbers or bounded-degree polynomials with floating point coefficients approximating continuous functions)

  • those that somehow enclose the exact entity, usually using a pair of endpoints

Type classes are provided to capture:

  • the partial, sometimes semidecidable, natural ordering (<=) used in relation to nearness

  • the partial, sometimes semidecidable, refinement ordering (⊑) used in relation to enclosure