Meshing, Geometric Modeling and Numerical Simulation 3

Chapter 1Data and Basic Techniques

The concept of data structure has several meanings. Within the context of this book, three meanings will be examined. We shall therefore examine what basic data structures are, and how abundantly they are used in the development of any algorithm and, also, as the very components of other higher level structures. As indicated, algorithms rely on these structures, but make extensive use of so-called basic techniques that we are also going to discuss. Internal and external structures will also be considered. Internal structures depend specifically on the algorithm and are only known to it, whereas external structures are used as interfaces between algorithms (software programs) and are thus known to (and usable by) all players of the computational chain (meshers, solvers, visualization tools, etc.). Hereafter, the way that these structures are implemented is not in question, but it will be seen that, more often than not, one or more arrays (a particularly simple structure) are employed.

Concerning basic structures, rather than giving an abstract description, which can be found in any good reference, we shall make an effort to consider the problem from a practical point of view, linking to questions about meshes and their utilization in numerical simulations. Within our specific context, a good understanding of what these structures are and what they are capable of doing when coupled with a few basic techniques can provide ideas for different ...