A file variable selects a particular datafile from the model. A file parameter can be set to a file variable. You can use a file variable to parameterize a file parameter for sweeping a MICHELLE simulation.
To create a file variable from a file parameter, first click the ellipsis button("...") to the right of the parameter in the property grid.
The following dialog appears.
Click the New button. After the variable is created, select it from the list to use it in the parameter. Then in the Variables control, you can choose which datafile to set the variable to which will control the parameter.