Section: New Software and Platforms

YALTA

Participants : Catherine Bonnet [correspondent] , Hugo Cavalera, André R. Fioravanti [UNICAMP] , Jim Pioche [SciWorks Technologies] .

The YALTA toolbox is a Matlab toolbox dedicated to the study of classical and fractional systems with delay in the frequency-domain. Its objective is to provide basic but important information such as, for instance, the position of the neutral chains of poles and unstable poles, as well as the root locus with respect to the delay of the system. The corresponding algorithms are based on recent theoretical results (see, for instance, [70] and [79] ) and on classical continuation methods exploiting the particularities of the problem [80] , [81] .

For classical delay systems, a Pade2 approximation scheme is available as well as a finite-dimensional approximation of the system.

Recently, some optimizations and features have been added. For instance, the main software function has been split into several procedures, allowing some calculus such as finding the position of the neutral chains to be processed independently of more computationnally expensive ones (for instance determining the root locus with respect to the delay of the system). In parallel, software documentation has been rewritten.

Binaries are freely available at http://yalta-toolbox.gforge.inria.fr/ .

The YALTA GUI (graphical user interface) is a graphical application developed in Python that interacts with the Matlab toolbox 5.7 . User actions are performed through intuitive graphic elements (dialog boxes, icons, menus, scroll bars) in order to capitalize on the functionalities of YALTA. This software, still in development, is based on PyQt, a Python binding of the cross-platform GUI toolkit Qt (C++).