Exact Computation with leda_real — Theory and Geometrie Applications

  • Kurt Mehlhorn
  • Stefan Schirra


The number type leda_real provides exact computation for a subset of real algebraic numbers: Every integer is a leda_real, and leda_reals are closed under the basic arithmetic operations +, -, *, / and k-th root operations. leda_reals guarantee correct results in all comparison operations. The number type is available as part of the LEDA C++ software library of efficient data types and algorithms (LEDA, Mehlhorn and Nüher 2000). leda_reals provide user-friendly exact computation. All the internals are hidden to the user. A user can use leda_reals just like any buHt-in number type. The number type is successfully used to solve precision and robustness problems in geometric computing (Burnikel et al. 2000, Seel). It is particularly advantageous when used in combination with the computational geometry algorithms library CGAL.


Voronoi Diagram Computational Geometry Number Type Algebraic Integer Geometric Program 
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© Springer-Verlag Wien 2001

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  • Kurt Mehlhorn
  • Stefan Schirra

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