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Questions tagged [automaton]

An automaton is a mathematical object describing an abstract machine with a finite set of states and transitions between these that runs on sequences of inputs consisting of letters (or symbols) picked from an alphabet.

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Is this transformation from a NFA to a DFA correct?

I am studying for an exam and came up to this task in the picture usually the transformation from a NFA to a DFA is easy to me. I create a transition table from the NFA and for every "new" combined state, i create a new column and so on (looking at…
ArdianH101
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How can I visualize an XML file as a graph?

The following XML code represents a typestate model. …
Alex
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How to understand the process of DFA construction in KMP algorithms

I'm learning KMP algorithm in the Book Algorithms 4th. I could understand most of the algorithm but have been stuck at process of dfa construction for a couple of days. Take the pattern ABABAC for example. When there's a mismatch at C(state of dfa…
ProtossShuttle
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How do I freeze a goal for a list of variables?

My ultimate goal is to make a reified version of automaton/3, that freezes if there are any variables in the sequence passed to it. i.e. I dont want the automaton to instantiate variables. (fd_length/3, if_/3 etc as defined by other people here on…
user27815
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test RegExp on large number of strings

I have a lot of strings (maybe about 50k-1M, all of them not too long, maybe 1-20 chars). Now I get any RegExp and I need to return a list/iterator of all matching strings. This must be as fast as possible. What are good index structures to do…
Albert
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Prove that it is undecidable whether a Deterministic LBA accepts an infinite number of inputs

Deterministic Linear Bounded Automaton (LBA) is a single-tape TM that is not allowed to move its head past the right end of the input (but it can read and write on the portion of the tape that originally contained the input). How can I prove that…
Dan Webster
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Regex for a word of a concatenation of 'a's and 'b's. a appears exactly n*2 times in a word and 'b' exactly n*3 times

I need to create a NFA (or DFA, don't know which it is going to be yet) for this language: L(A) = { w ∈ {a,b}* | count(w, a) = 2i, count(w, b) = 3j, i, j ∈ ℕ } count(w, z) defines how often a letter z appears in the word w. In this case it's a…
user1202727
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Simple enum for java automaton

I'm trying to implement this automaton example : http://www.javacodegeeks.com/2012/03/automaton-implementation-in-java.html. However, an error keeps on being displayed while running the program : Exception in thread "main"…
Fabrice Sopoglian
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More powerful than a DFA but less than a DPDA

Is there anything that is more powerful than a finite automaton but less powerful than a deterministic push down automaton?
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Is the dk.brics.automaton package thread safe?

Apache Lucene uses a modified form of the Brics automaton package. But is Brics thread safe? More specifically, can it safely handle multiple, concurrent automaton instances from different threads - without blocking?
Ashwin Jayaprakash
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Getting values from previous "row" in 2D C array

I'm working on a 1D Game of Life (based upon the rules set out here at Mathworld). Essentially, each generation is represented as a row of 0's or 1's (dead or alive) and the next generation is created based upon the binary representation of a "rule"…
Richard Martinez
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Non deterministic state machine using PyTransitions?

I am using pytransitions and have come across the need to have several states which are unrelated with others, and would make much sense to model using a non deterministic state machine, which is mathematically equivalent. I would like something…
Gulzar
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Peg Solitaire / Senku solution algorithm

I need to program a solver for the game of Peg solitaire / Senku There's already a question here but the proposed answer is a brute force algorithm with backtracking, which is not the solution I'm looking for. I need to find some heuristic to apply…
Petruza
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Determining whether a nondeterministic finite automaton accepts every possible string

Given an NFA, is there a way to determine whether it accepts all strings constructed from its alphabet, without having to iterate over the infinite set of possible strings?
Hans von Olo
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Existance proofs with polymorphic types

I am trying to formalize the proof that DFA are closed under union, and I have got so far as proving "∀ ℬ. language ∪ language ℬ = language (DFA_union ℬ)", but what I would actually like to prove is ∀ ℬ. ∃ . language ∪ language ℬ = language . I…
Zoey Sheffield
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