Model Definition

ParX models are represented as a set of implicit equations that must be zero in the solution. There is no separation between independent and dependent variables. In combination with the availability of internal (i.e., auxiliary) variables, this allows for a much wider scope of models without the need for internal iteration.

A ParX model definition file has the .parx file extension, and must contain only plain text. Be cautious which editor you use, because editors such as TextEdit are quick to insert special formatting codes, such as smart quotes, which will throw weird syntax errors when the model file is loaded into ParX. Note: as of version 2.5, the model compiler handles smart quotes more gracefully by treating them as the normal variant. This means, however, that they can no longer be used as part of a symbol name.

The model description consists of three parts: the header section for the model attributes, the declaration section, and the equations section.