Semirings and tree-to-graph-to-tree transductions
نویسنده
چکیده
It is shown that top-down tree transducers are as powerful as sharing-free tree-to-graph-to-tree transducers as far as the computation of functions is considered whose codomain is a semiring.
منابع مشابه
A Comparison of Tree Transductionsde ned by Monadic Second Order
Formulas from monadic second order (mso) logic with one and two free variables can be used to deene the nodes and edges (respectively) of a graph, in terms of a given graph. Such mso deenable graph transductions play a role in the theory of graph grammars. Here we investigate the special case of trees. The main result is that the mso deenable tree transductions are exactly those tree transducti...
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عنوان ژورنال:
- Electr. Notes Theor. Comput. Sci.
دوره 2 شماره
صفحات -
تاریخ انتشار 1995