The Model Pane
To load a ParX model choose File > Open Model… (⌘O) to show the Open File Dialog.
Select the desired .parx file and choose to open the file.
Alternatively, select the model file in the Finder and choose
Open With and select the ParX.app from the App list.
Or, in the Finder, drag and drop a model file directly on the model pane.
When the model file is loaded, the model pane will display the model interface:
the interface variables and the parameters.
The model interface shown here has two variables:
x and y, and four parameters c0 to c3.
It models a third order polynomial equation.
Before you can draw the model in the graphing pane, the axis’ must be chosen. The first selected variable is taken as the x-axis of the graph, or sweep variable, in this example the x variable of the model. Since the model has only two variables, this places the y variable along the y-axis.
The plot range for the sweep variable is specified as:
-10 ≤ x ≤ 10 in 100 steps. (Note that this results in 101 points).
The model parameters each get a value, a lower bound and an upper bound. The slider is connected to the parameter value, and allows it to be varied between the bounds. When the model is first loaded these fields get set to the default values as specified in the model file.
After extracting the parameter values from the measured data, the parameters acquire an additional field that expresses the precision of the result.
Finally, each parameter has a fixed button that locks its value during extraction.
When the model definition is modified in the background in a text editor,
the model must be reloaded before the changes are reflected in the graph.
Choose File > Reload Model (⌘R).
If the model interface is unchanged (same names) the values will be retained;
else the default values will be restored.
This mechanism allows you to experiment with the model equations interactively.
The graph is drawn as soon as all the variables are specified.
The graph is automatically updated when the model variable ranges or parameter values are changed. When using the parameter slider to change the parameter value, the model curve(s) and the axis' will be animated to show the effect.
Save the Settings
The interface values of the model can be saved to file for later re-use.
Choose File > Save Model…(⌘S) and supply a file name in the Save dialogue.
The file is saved with the .prxs extension.
The settings can be recreated by choosing File > Open Model… (⌘O) and opening
the file containing them.
Opening a .prxs file in the Finder will also load the settings,
as will drag and dropping the file on the model pane.
Exporting the Model
The interface values can be exported
to a .csv file, a .tsv file, or a .txt file.
The .tsv file is UTF16 encoded for better compatibility with Excel.
Choose File > Export Model To,
and select a file location in the file Export dialog.
This functionality is provided mainly for interfacing with other software.
Exporting the Simulation Data
The simulated model data (or model curves) can be exported
to a .json file, a .csv file, or a .tsv file.
The .tsv file is UTF16 encoded for better compatibility with Excel.
Choose File > Export Simulation To,
and select a file location in the file Export dialog.
This functionality is provided mainly for testing purposes, so when developing a model, its performance can be tested first with synthetic data. The error intervals of the simulated data points will always be zero.