Dfa

A DFA is a deterministic finite automaton, a simple model of computation

Nfa

An NFA is a nondeterministic finite automaton, a mathematical model of computation that decides membership in regular languages.

Easier representation equivalent

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"Because representation of a given problem with a nfa is from question Non-deterministic finite state machines in software development? |

"Stephen string search or a compiled dfa you can construct stephen string search or a compiled dfa from an nfa from question Faster way of searching a string in text files |

Slower powerful engine

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"Perl uses nfa which is from question Is it faster to use alternation than subsequent replacements in regular expressions |

"Regex is a nfa and is as such in most cases from question Rewrite IsHexString method with RegEx |

Simple transitions smaller

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"In fact because you are eliminating the redundancy of epsilon transitions many simple dfa s actually get from question DFA based regular expression matching - how to get all matches? |

"The dfa from question A succinct description of NFA to DFA conversion? |

Others

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The net effect is that the backtracking implementations i like that name better than traditional nfa are slightly more from question If NFA and DFA were equivalent, why would we have two engines for regex? |

Dfa is a from question Parallel regex matching with NFA vs DFA? Which one is faster? |

As a result a posix nfa engine is slower than a traditional nfa engine and when using a posix nfa you cannot favor a shorter match over a longer one by changing the order of the backtracking search;traditional nfa engines are favored by programmers because programmers are more from question DFA vs NFA engines: What is the difference in their capabilities and limitations? |

If it can be practically determinized this give you a dfa that can be exponentially from question Match Regular expression from a dictionary in C# |

Generally speaking dfa is from question Parallel regex matching with NFA vs DFA? Which one is faster? |

If you have a regular expression without any optional such as ab the nfa graph doesn t have to contain any epsilon edges;an important concept in nfa simulation and nfa to dfa from question Converting NFA to DFA without epsilon transition function |

If it finds a match then it goes back and matches the full regex using an nfa engine i think traditional non-posix but starting at the location where the simplified match occurred;this is much faster for both non-matches and matches than a straight nfa engine but still lets you use all the things in an nfa that a dfa from question Which regular expression engine type does R use as a standard? |

If we express combinations of states in an nfa as states themselves we ve got a dfa with a lot from question DFA vs NFA engines: What is the difference in their capabilities and limitations? |

At the same time the compilation phase for a dfa is from question How much faster are regular expressions processed in C/Java than in Python? |