An Aho-Corasick based assessment of algorithms generating failure deterministic finite automata

The Aho-Corasick algorithm derives a failure deterministic finite automaton for finding matches of a finite set of keywords in a text. It has the minimum number of transitions needed for this task. The DFA-Homomorphic Algorithm (DHA) algorithm is more general, deriving from an arbitrary complete deterministic finite automaton a language-equivalent failure deterministic finite automaton. DHA takes formal concepts of a lattice as input. This lattice is built from a state/outtransition formal context that is derived from the complete deterministic finite automaton. In this paper, three general variants of the abstract DHA are benchmarked against the specialised Aho-Corasick algorithm. It is shown that when heuristics for these variants are suitably chosen, the minimality attained by the Aho-Corasick algorithm can be closely approximated. A published non-lattice-based algorithm is also shown to perform well in experiments