Ignacio Martinez (U Chicago/Argonne, Vensim distributor, and all around nice guy) has developed a nifty tool that exploits Vensim’s open text file format and .dll to make very thorough, browsable model documentation.
It’s incredibly simple to use. Just unzip the archive, fire up the .exe, and point it at a model (.mdl format; it’ll also read some information out of an accompanying published .vpm, if there is one, but that’s not needed):
It creates a set of html documentation in your model’s directory, with nifty features like the following:
A master table of results
A list of overly-complex equations
A table of variable usage in model views (very useful for finding hidden structure)
A hyperlinked equation listing, with various ordering options
You can download it here. SDM-Doc-4_3_5.zip Be aware that this is unsupported beta software, so use at your own risk (I don’t think there is any, but I think I need to say that).
Latest and greatest: SDM-Doc-4_6_01.zip
This is now hosted as an open source project at systemdynamics.org; see http://tools.systemdynamics.org/sdm-doc/ for the latest.