Figure 1: The project file tracks files opened into or output from the program, and those output from the program as well. Note there are some other program outputs (plot bitmaps, exported tables, etc.) that are not tracked with the project.

The modeling process is organized by project. A project is a text-based file that does the following jobs.

  • track all files input (this is primarily any file processed by the program call command or opened into the project using the i Open Into Project dialog)

  • track all files output (this is primarily all saved model states)

  • track/indicate the current state of all input and output files within the program (which data files are open, which model state is the current state, etc.)

  • store project settings

  • store the program layout

  • store “project” objects (this is a range of items that includes plots and named filters)

  • set the working directory

  • store program environment information (program name, version, and revision information, for instance)

Project Resources

Files tracked by the project are not *embedded* within it. Moving project files by some method outside the program (e.g., with Windows Explorer) will break the links being maintained by the project. With items tracked by the project, it is best to do file management tasks (moving or renaming) within the program.

Some project resources are stored as files on the file system, others are contained within either the project file or in a saved state of the model. When referring to these resources they are spoken of as “belonging to” or as “part of” the program, the project, or the model. Keeping the distinctions here straight is one of the trickier parts of project management.

Table 1: Resource Storage in the Program


Part of

Saved In

configuration settings


    Options Dialog

project file (*.prj)


    file system

data file (*.dat, *.fis, *.py)


    file system



    project file

model state (*.sav)


    file system

results file (*.rslt)


    file system

sketch set


    model state file(s)

building blocks set


    model state file(s)

geometry set


    model state file(s)

Project Access at Startup

When the program starts, the startup dialog may be set to open the most recent project used or a start a new one. The preferred option may be set by the user in the Options dialog‘s “Startup” section.

Project Packaging

The Bundle command from the Tools menu is a utility for packaging projects (both the project file and the resources it tracks) into a single compressed archive file. The bundle file is useful for transfer of projects between users, for obtaining technical support, or for archival purposes.