# Reading Setup Files

One of the main features of Schnek is the ability to read and parse setup files and initialise simulation parameters from the values specified in the setup file. Schnek is quite versatile. The setup file can contain mathematical expressions and the user can even define her own variables inside the setup file to use inside the expressions.

You can initialise scalar variables of the standard types int, double, and std::string. It is also possible to fill Grids from the expressions supplied in the input file. You can allow the user to specify a time-varying function that specifies a parameter that varies during the course of the simulation run.

Finally, it is easy to extend the reader to accept additional functions.

This section covers the following topics.