Revisions allow you to track differences between multiple versions of your content, and revert back to older versions.
The R for generating a path diagram from a model is straightforward:
(currently for RAM models only)
If you leave parameter 2 blank, the dot file will be output into the R console.
There's an example of usage here
The output is just a linguistic description of the nodes and edges of your diagram - to visualise it, this must be processed by an application such as graphvis.
Other programmes that can read .dot include Omnigraffle.
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