CONSTRUCTION OF TREE AUTOMATA FROM REGULAR EXPRESSIONS

摘要

Since recognizable tree languages are closed under the ra-tional operations, every regular tree expression denotes a recognizable tree language. We provide an alternative proof to this fact that results in smaller tree automata. To this aim, we transfer Antimirov's partial derivatives from regular word expressions to regular tree expressions. For an analysis of the size of the resulting automaton as well as for algo-rithmic improvements, we also transfer the methods of Champarnaud and Ziadi from words to trees.