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Prepare a folder in your file system, where you can clone the repositories to. In order to compile JADEYADE, you have to compile all three projects at least once before you can compile YADE on its own. This is necessary for the YADE build to be able to resolve its dependencies from your local maven repository.
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At this point you already have all the library files to update an exisiting JADE YADE installation in your system.
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