Numerical Modelling with Python and XML

In this paper we continue the development of our Python-based package for the solution of partial differential equations using spatial discretization techniques such as the finite element method (FEM), but we take it to a higher level using two approaches: First we define a "Model" class object which makes it easy to break down a complex simulation into simpler sub-models, which then can be linked together into a highly efficient whole. Second, we implement an XML schema in which we can save an entire simulation. Thisn allows implementing check-pointing and also graphical user interfaces to enable non-programmers to use models developed for their research. All this is built upon our escript module, which makes it easy to develop numerical models in a very abstract way while using the computational components implemented in C and C++ to achieve extreme high-performance for time-intensive calculations