## Section: Software

### Endymion

Participant : José Grimm.

The development of *Endymion* ,
http://www-sop.inria.fr/apics/endymion/index.html
has been stabilized. It is a software licensed
under the CeCILL license version two, see
http://www.cecill.info . It has been
registered under the number
IDDN.FR.001.310002.000.S.P.2009.000.10000 at the the APP
It was developed on Linux, but works as well on
MacOS.
The core of the system is formed by a library that handles numbers
(short integers, arbitrary size rational numbers, floating point numbers,
quadruple and octuple precision floating point numbers, arbitrary precision
real numbers, complex numbers), polynomials, matrices, etc.
Specific data structures for the rational approximation algorithm *arl2*
and the bounded extremal problem *bep* are also available. One can
mention for instance splines, Fourier series, Schur matrices, etc.
These data structures are manipulated by dedicated algorithms (matrix
inversion, roots of polynomials, a gradient-based algorithm for minimizing
, Newton method for finding a critical point of , etc), and
input-output functions that allow one to save data on disk, restore them, plot
them, etc. The software is interactive: there is a symbolic
interpreter based upon a Lisp interpreter. For instance the
coefficient of z^{2} in P can be obtained via Lisp syntax
`(getcoef P 2)` or modified via the symbolic syntax
`P[2]++` .