In this paper, we present GASPARD (Graphical Array Specification for Parallel and Distributed computing), our visual programming environment devoted to the development of parallel applications. Task and data parallelism paradigms of parallel computing are mixed in GASPARD to achieve a simple programming interface. We use the printed circuit metaphor. The programmer specifies tasks and instantiates by plugging them into a slot (task parallelism). Data parallelism is achieved by specifying the data the task uses. By mixing textual and visual programming, we achieve a convenient interface useful for scientific programming. The interface is also well suited for meta-computing deployment. This kind of programming is very useful for numerical simulation.