A software package for the simulation and investigation of dynamical systems called AnT 4.669 will be presented in this paper. Due to its flexible architecture, the AnT 4.669 software package is able to cope with dynamical systems belonging to various classes, such as ordinary and recurrent maps, ordinary, delayed, functional and partial differential equations currently with only one spatial component. Further supported classes are: coupled maps, coupled ordinary and delayed differential equations lattices as well as hybrid systems, stochastic systems and external data. Many investigation methods are implemented in the AnT 4.669 software package, like for instance general trajectory evaluations, basic statistics, period and region analysis, calculation of bifurcation diagrams, spectral analysis, principal component decomposition, symbolic sequence evaluation and the calculation of Lyapunov exponents using two different algorithms. Additionally a generalized implementation of Poincaré sections and Poincaré return maps exists, with several pre-implemented conditions and an additional possibility with a user defined condition. Furthermore, the box-counting based calculation of the invariant measure, the entropy and several fractal dimensions are available. Additionally, a collection of investigation methods based on the calculation of the symbolic image of a dynamical system is implemented. Using these methods, one is able to determine stable and unstable invariant sets, stable and unstable manifolds of fixed points and periodic orbits, as well as basins of attraction. For dynamical systems discrete in time, the calculation of backward orbits is implemented.

Another important feature of the AnT 4.669 software package, is the capability to perform so-called scan runs, that is the ability to investigate a dynamical system by varying one, two or even more relevant influence quantities, such as the control parameters, initial values, or even some parameters of the investigation methods, which is interesting in the context of optimizing the results obtained by an investigation method. When dealing with scans in high-dimensional parameter and/or state spaces, a significant advantage of the AnT 4.669 software package is the distributed computing capability. This capability is based on a client/server architecture and allows the calculation of time consuming scan runs on an arbitrary number of computing nodes (both, in homogeneous clusters as well as in heterogeneous networks).

The AnT 4.669 software package possesses also an interactive visualization module, based on the OpenGL standard, which supports animations of trajectories and an intuitive graphical user front-end, that guides a user of the system through the complex initialization phase of a simulation run.

Finally there exists a web front-end to the AnT computation engine, which allows the remote execution of simulation runs.

AnT 4.669 is free software (published under the GPL) and is available for several UNIX as well as Windows platforms. More information about the AnT-project can be found on the website: www.AnT4669.de.