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Two-Dimensional
Tree Recognizer


Yield Projecting Algorithm

After determining how we are going to represent the spines and heads of multidimensional trees in both the internal and external form, we were able to write a program that would take an n-dimensional tree and collapse it to return the (n-1)-dimensional tree with the same yield. Using this, we could easily extend it to take an n-dimensional tree and return it's string yield.

The algorithm works by recursively traversing down the tree from the root to the leaves. While most of our previous algorithms have used a bottom-up method, we ran into problems and decided to use a top-down method (solutions to these problems were not explored, we simply decided to take the easier route). At each node with an n-dimensional successor, the node is replaced with it's (n-1)-dimensional yield, and the node's successors in the other dimensions are hung on the proper heads of the new yield. At each node without an n-dimensional yield, the algorithm is recursively run on its other successors. When the algorithm returns, the tree has been transformed from an n-dimensional tree to an (n-1)-dimensional tree with the same yield.


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Last updated: Monday, 26-Jul-2004 14:22:53 EST
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