4.5 The Parameter Administration

The parameter administration is a crucial aspect regarding the usability of the system. As the assembly and solver module can be controlled by more than hundred parameters, it would be inconvenient if all of them had to be specified as arguments. For that reason, all parameters are centralized in one structure, which has a threefold purpose:

1. It provides a method of passing data to the solver function that influence the behavior of the function. This includes the choice of a proper solver, preconditioner, sorter, and scaler, the choice of maximum limits for memory allocation and time consumption, and other parameters.
2. It supports the persistence of data that has to be conserved between multiple runs of the solver function on the same type of equation system, for example the repeated solving during the Newton iteration. In such cases, information about the previous solving step is used to improve the solution speed on the next call to the solver function, for example by choosing proper preconditioning parameters.
3. It provides a method of returning statistical data about the solution process to the simulator.