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The first thing that is done is the graph import. Since the algorithm works with KIML it is necessary to import the graph that should be layouted with Mr. Tree. The important data structure (KGraph) is a comparatively complex structure. The tree algorithm does not need all parts of this data structure, so the parts that are necessary are converted into a less complex data structure, the MrTGraph data structure (TGraph), which is described through a class diagram below. As mentioned before, Mr. Tree runs on that data structure. After execution of the tree algorithm, the TGraph gets reconverted to a KGraph in a graph export phase, so that everything works fine with KIML.
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