## Section: Software

### MPFR

Participants : Guillaume Hanrot, Philippe Théveny, Paul Zimmermann [ contact ] .

Mpfr is one of the main pieces of software developed by the Cacao team. Since end 2006, with the departure of Vincent Lefèvre to Ens Lyon, it has become a joint project between Cacao and the Arenaire project-team (Inria Grenoble - Rhône-Alpes). Mpfr is a library for computing with arbitrary precision floating-point numbers, together with well-defined semantics, and is distributed under the Lgpl license. In particular, all arithmetic operations are performed according to a rounding mode provided by the user, and all results are guaranteed correct to the last bit, according to the given rounding mode.

Several software systems use Mpfr , for example: the Gcc and Gfortran compilers; the Sage computer algebra system; the Kde calculator Abakus by Michael Pyne; cgal (Computational Geometry Algorithms Library) developed by the Geometrica project-team (Inria Sophia Antipolis - Méditerranée); Gappa, by Guillaume Melquiond; Genius Math Tool and the Gel language, by Jiri Lebl; Giac/Xcas, a free computer algebra system, by Bernard Parisse; the iRRAM exact arithmetic implementation from Norbert Müller (University of Trier, Germany); the Magma computational algebra system; and the Wcalc calculator by Kyle Wheeler.

The main developments in 2009 were: the release of version 2.4.0 (andouillette sauce moutarde) in January, with the new name GNU Mpfr , the release of GNU Mpfr 2.4.1 in February, the CNC'2 summer school in June, and the end of the contract of Philippe Théveny in September.

All those developments were done in the context of the
ODL (*Opération de Développement Logiciel* )
MPtools, supported by Inria from September 2007 to
August 2009.