Within Trelis there is support for a programming language called APREPRO (An Algebraic Preprocessor for Parameterizing Finite Element Analyses). Included here is a summary of the APREPRO functionality included within Trelis. This is a summary of the full APREPRO user's manual (PDF).

Note: APREPRO variables can be created and modified from the GUI. Enable/disable the editor from the View/Aprepro editor menu option. The editor is a docking window and can be placed anywhere in the GUI.