A regular MATLAB m-file can work as gfit model. The file should have its function definition in the first line. Function output arguments correspond to model's output variables. Function input arguments should contain all or none of the model variables. Comment lines that follow function definition are used as model comments.
Model description distinguishes gfit model from other m-files and
allows gfit to use the model for data analysis. Model description
follows the model comments and should be enclosed in
<gfitModelDescription version="100"> and
</gfitModelDescription> tags. All lines of model description
should be commented out and thus ignored by MATLAB environment. MATLAB comment
% appearing in the beginning of the line are, in turn, ignored by
gfit when it reads model description.
The language for m-file model description attempts to be both expressive and human-readable (XML is an alternative language for model description). The following simple model serves as an illustration. The major part of model description defines variables and their relationships. The variables are defined through their attributes (see complete list of variable attributes).
Definitions for variable attributes can be divided between several tables to
present all the information in the most compact and intuitive manner. The first
row of each table begins with word
variable followed by the names
of variable attributes specified in that table. Each subsequent line begins
with variable name followed by variable attribute values. All variable
attributes and their acceptable values are listed