Editing Deterministic finite automaton (section)

===Complete and incomplete===
According to the above definition, deterministic finite automata are always ''complete'': they define from each state a transition for each input symbol.

While this is the most common definition, some authors use the term deterministic finite automaton for a slightly different notion: an automaton that defines ''at most'' one transition for each state and each input symbol; the transition function is allowed to be [[partial function|partial]].<ref name="Mogensen">{{cite book | last=Mogensen | first=Torben Ægidius | title=Introduction to Compiler Design | chapter=Lexical Analysis | series=Undergraduate Topics in Computer Science | publisher=Springer | location=London | year=2011 | doi=10.1007/978-0-85729-829-4_1 | page=12| isbn=978-0-85729-828-7 }}</ref> When no transition is defined, such an automaton halts.