Imagine a user has written some methods for creating and editing starting triangulations for her/his numerics. Some buttons are needed to invoke these methods and some flags and rulers to control what the methods do when they are called, additionally a basic triangulation to start with might be useful. All this could be added to the GRAPE program in the main routine, but then the triangulation and buttons and rulers are always present, they fill up the menus even if the user is working on something else and they are not needed. A separate main program could be created for each application, but if two packages are needed at the same time a new main program must be created with a copy of both codes. This gets more complicated with each application that is added, and if packages are exchanged between several users it gets unmanageable.
The solution for these problems are projects. A project is a collection of classes, methods and interactive elements (a ``user-interface''). Projects can interactively be added to and removed from the system, thereby adding resp. removing the classes and methods and modifying the interactive environment. A project may depend upon other projects which are loaded resp. unloaded automatically with the project. New objects can be inserted into the data hierarchy when a project is added.
Copyright © by the Sonderforschungsbereich 256 at the Institut für Angewandte Mathematik, Universität Bonn.