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| | Pushdown automaton - Wikipedia, the free encyclopedia |
 | | If a deterministic finite state machine is used, then the result is a "deterministic pushdown automaton" (DPDA), a strictly weaker device. | | | Pushdown automata choose a transition by indexing a table by input signal, current state, and the top of the stack. | | | The (underlying) finite automaton is specifically a nondeterministic finite state machine, giving what is technically known as a "nondeterministic pushdown automaton" (NPDA). |
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http://en.wikipedia.org/wiki/Pushdown_automaton
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| | Abstract paper Teams of Pushdown Automata |
| | If all stacks are empty when the input word has been completely read, then this word is part of the language accepted by the team pushdown automaton. | | | In a team pushdown automaton, several pushdown automata work as a team on the input word placed on a common one-way input tape. | | | At any moment in time one team of pushdown automata, each with the same symbol on top of its stack, is active: each pushdown automaton in the active team replaces the topmost symbol of its stack and changes state, while the current input symbol is read from the input tape by a common reading head. |
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http://fmt.isti.cnr.it/~mtbeek/abstractcm-pda.html
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| | Flow-Based Programming: Relationships with Compilers |
| | Since CFGs are more general than right linear grammars, they require a more complex type of automaton to process them: the "pushdown automaton" (PDA), which has, in addition to its input tape, memory in the form of a "pushdown stack". | | | A pushdown automaton will have "stack states" in addition to "automaton states": in this example the automaton state is trivial, as there is really only a "normal" state ( q0) and a "final" state ( qf), to enable the automaton to stop. | | | In Aho and Ullman's 1972 book they show that a regular expression can be parsed by a deterministic one-way finite automaton with one tape, usually referred to simply as a "finite automaton". |
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http://www.jpaulmorrison.com/fbp/compil.htm
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| | Home-Adhar |
| | The idea of an automaton with a stack as auxilliary storage is formalized in the notion of a pushdown automaton, or PDAs. | | | Adding non-determinism to this computational model means that the automaton is allowed to change its states in a way that is only partly determined. | | | The required storage device need not be a general-purpose one; a simple stack, or "pushdown store" would be enough. |
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http://people.uncw.edu/adharg/courses/csc360/Fall2003/module3.html
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| | Pushdown automaton - Wikipedia, the free encyclopedia |
| | Nondeterministic finite state machine (resulting in a nondeterministic pushdown automaton or NPDA) since deterministic pushdown automata cannot recognize all context-free languages. | | | linear bounded automaton is a device which is more powerful than a pushdown automaton but less so than a Turing machine. | | | The finite automaton in question is usually a |
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http://en.wikipedia.org/wiki/pushdown_automata
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| | automata.txt |
| | Pushdown automata are merely finite automata endowed with access to an unbounded stack, and bounded linear automata are Turing machines whose read/write head is not allowed to leave the region of tape where the input is given. | | | Theory of Automata------------------ Intuitively a finite automaton is a mathematical model of computing device that has discrete inputs and outputs as well as a finite set of internal states. | | | The automaton takes as input a sequence of symbols drawn from an alphabet of symbols, and after reading each symbol in sequence, the automaton makes a transition from its current state to a new state depending on the value of the input read. |
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http://keck.ucsf.edu/~surya/automata.txt
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| | PlanetMath: non-deterministic pushdown automaton |
| | A non-deterministic pushdown automaton (or PDA) is a variation on the idea of a non-deterministic finite automaton (NDFA). | | | See Also: context-free language, non-deterministic finite automaton, automaton | | | When a PDA halts, it is considered to have accepted the input string if and only if there is some final state where the entire input string has been consumed and the stack is empty. |
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http://www.planetmath.org/encyclopedia/PushdownAutomaton2.html
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| | LANGUAGES, GRAMMARS, AUTOMATA & QUANTUM ANALOGS |
| | Compilers for computer languages are approximations to an ideal finite state pushdown automaton, a foible being that they can "blow their stacks". | | | Automaton An automaton is the heart of a sequential machine, that which deals only with inputs and states. | | | A Nondeterministic Finite Automaton (NFA) There can be several *simultaneous* transitions for each possible input. |
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http://graham.main.nc.us/~bhammel/MATH/autom.html
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| | PlanetMath: non-deterministic finite automaton |
| | See Also: deterministic finite automaton, automaton, regular language, context-free language, language, non-deterministic pushdown automaton | | | A non-deterministic finite automaton (or NDFA) can be formally defined as a 5-tuple | | | Cross-references: simple, generate, regular expression, language, regular languages, represent, circles, vertex, arrow, edges, directed graph, entire, current, operation, deterministic finite automaton, transition function, automaton, strings, alphabet, states, finite |
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http://planetmath.org/encyclopedia/NDFA.html
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| | DRUM: Item 1903/594 |
| | In order to couple the external stack to the neural network, an optimization method is developed which uses an error function that connects the learning of the state automaton of the neural network to the learning of the operation of the external stack. | | | Though many approaches have been discussed, one obvious approach to enhancing the processing power of a recurrent neural network is to couple it with an external stack memory - in effect creating a neural network pushdown automata (NNPDA). | | | To minimize the error function using gradient descent learning, an analog stack is designed such that the action and storage of information in the stack are continu... |
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http://hdl.handle.net/1903/594
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| | REVEAL.ORG - First Online Java Class Decompiler and Obfuscator |
| | The non-deterministic pushdown stack automaton simulator allows students to program their PDAs and watch them execute. | | | Another Pushdown Stack Automaton (EH9-3) - The third in a suite of instructional tools for learning about recognizers. | | | There is text version for instructors to use for grading assighments. |
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http://www.jreveal.org/cgi-bin/resource.pl?resid=2700
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| | Chomsky's hierarchy of grammars |
| | The class of languages generated by type 2 grammars is exactly the class of languages recognized by pushdown automata (PDA, | | | Languages generated are recognized by Turing machines (automata that read from and write on an endless tape, which will be defined in section 4.3.1). | | | The PDA is said to accept an input string from |
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http://www.dlsi.ua.es/~mlf/nnafmc/pbook/node46.html
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| | References |
| | Fast recognition of pushdown automaton and context-free languages. | | | algorithm for minimizing the states in a finite automaton. | | | An efficient algorithm for determining the convex hull of a finite planar point set. |
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http://www2.toki.or.id/book/AlgDesignManual/BOOK/BOOK5/NODE232.HTM
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| | pushdown automaton |
| | Definition: A restricted Turing machine where the tape acts as a pushdown store (or stack, where only the latest element can be read), with an extra one-way read-only input tape. | | | Note: From Algorithms and Theory of Computation Handbook, page 24-19, Copyright © 1999 by CRC Press LLC. | | | HTML page formatted Thu Jun 10 09:40:48 2004. |
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http://www.nist.gov/dads/HTML/pushdownautm.html
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| | pda_recog.txt |
| | */ else printf("\n\nNon-Deterministic Pushdown Automaton Verified.\n"); /* Debugging messages */ #ifdef debug printf("\nStates:\n"); print_stuff(mach_states, mst); printf("\nSymbols:\n"); print_stuff(symbols, sym); printf("\nStack Symbols:\n"); print_stuff(stack_symbols, stack); printf("\nFinal States:\n"); print_stuff(final_states, fstates); #endif /* Close the file and exit */ fclose(infile); exit(0); } /* Here we read the input, and according to what state it matches, we return a particular integer. | | | If the end of the file is reached, print an error message and break out of the loop. | | | (!sym)) { if(!mst) printf("Error: No states.\n"); if(!sym) printf("Error: No symbols.\n"); } else { ver = verify_transitions(input, mst, sym, stack, mach_states, symbols, stack_symbols, transitions, &trans); } } break; case 5: printf("Verifying starting state.\n"); if(start != -1) { if((!mst) |
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http://www.cs.earlham.edu/~bartlbe/pda_recog.txt
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| | Secure Internet Programming: Understanding Java Stack Inspection |
| | We show that there are a finite number of such statements, allowing us to represent the security state of the system as a pushdown automaton. | | | We also show that this automaton may be embedded in Java by rewriting all Java classes to pass an additional argument when a procedure is invoked. | | | This paper models the stack inspection algorithm in terms of a well-understood logic for access control and demonstrates how stack inspection is a useful tool for expressing and managing complex trust relationships. |
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http://www.cs.princeton.edu/sip/pub/oakland98.html
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| | Pushdown automaton |
| | The finite automaton in question is usually nondeterministic (resulting in a nondeterministic pushdown automaton or NPDA) since deterministic pushdown automata cannot recognize all context-free languages. | | | A linear bounded automaton is a device which is more powerful than a pushdown automaton but less so than a Turing machine. | | | A NPDA W can be defined as a 7-tuple: |
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http://www.sciencedaily.com/encyclopedia/pushdown_automaton
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| | Pushdown automaton - Wikipedia, the free encyclopedia |
| | For every context-free grammar, there exists a pushdown automaton such that the language generated by the grammar is identical with the language generated by the automaton. | | | Conversely, for every pushdown automaton there exists a context-free grammar such that the language generated by the automaton is identical with the language generated by the grammar. | | | The (underlying) finite automaton is specifically a nondeterministic finite state machine, giving what is technically known as a "nondeterministic pushdown automaton" (NPDA). |
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http://en.wikipedia.org/wiki/Pushdown_automaton
(655 words)
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| | Pushdown automaton - Wikipedia, the free encyclopedia |
| | A linear bounded automaton is a device which is more powerful than a pushdown automaton but less so than a Turing machine. | | | The (underlying) finite automaton is specifically a nondeterministic finite state machine, giving what is technically known as a "nondeterministic pushdown automaton" (NPDA). | | | Informally, a pushdown automaton is a finite automaton that can make use of a stack. |
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http://en.wikipedia.org/wiki/Pushdown_automaton
(655 words)
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| | Pushdown automaton - Wikipedia, the free encyclopedia |
| | A linear bounded automaton is a device which is more powerful than a pushdown automaton but less so than a Turing machine. | | | The (underlying) finite automaton is specifically a nondeterministic finite state machine, giving what is technically known as a "nondeterministic pushdown automaton" (NPDA). | | | Informally, a pushdown automaton is a finite automaton that can make use of a stack. |
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http://www.wikipedia.org/wiki/Pushdown_automaton
(547 words)
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| | Technical Report 2002/4 |
| | At any moment in time one team of pushdown automata, each with the same symbol on top of its stack, is active: each pushdown automaton in the active team replaces the topmost symbol of its stack and changes state, while the current input symbol is read from the input tape by a common reading head. | | | In a team pushdown automaton, several pushdown automata work as a team on the input word placed on a common one-way input tape. | | | If all stacks are empty when the input word has been completely read, then this word is part of the language accepted by the team pushdown automaton. |
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http://www.sztaki.hu/mms/gzipped/abstract2002per4.html
(228 words)
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| | formal-languages.txt |
| | Every (non-deterministic) pushdown automaton is equivalent to a deterministic pushdown automaton. | | | Every pushdown automaton can be simulated by a Turing machine. | | | Give at least one example of a method of constructing such a grammar from an automaton or such an automaton from a grammar. |
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http://www.mathcs.sjsu.edu/faculty/smithj/oldclass/288s05/formal-languages.txt
(796 words)
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| | Lehrstuhl für Informatik VII |
| | We show that it is decidable for a given visibly pushdown automaton whether it is equivalent to a visibly counter automaton, i.e. | | | In particular, this allows to decide whether a given visibly pushdown language is a regular restriction of the set of well-matched words, meaning that the language can be accepted by a finite automaton if only well-matched words are considered as input. | | | Visibly pushdown automata are special pushdown automata whose stack behavior is driven by the input symbols according to a partition of the alphabet. |
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http://www-i7.informatik.rwth-aachen.de/d/publications/pub-Loeding-abstracts.html
(1980 words)
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| | summary-fall01 |
| | However, the applet also allows the user to input graphs as Finite Automaton and Pushdown Automaton, and to test strings to see if they are accepted by the FA/PDA. | | | The graph shown above does not act as a Finite Automaton or Pushdown Automaton, since it does not have a start node or any accept nodes. | | | This is important when working with Finite Automata and Pushdown Automata. |
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http://www.cs.rpi.edu/~prestn2/summary-fall01.html
(1159 words)
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| | Binary Queries |
| | A pushdown automaton visits the nodes of a document in the same order in which they are encountered by an XML parser. | | | The reason why these two sets may not be equal is that by the time the pushdown automaton finishes visiting a node, it has not seen all the context of the node. | | | The processing model of a pushdown forest automaton is depicted in Figure 4. |
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http://www.mulberrytech.com/Extreme/Proceedings/html/2002/Berlea01/EML2002Berlea01.html
(4689 words)
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| | Declarator Parsing in Elsa |
| | Quick pushdown automaton refresher: A pushdown automaton is like a finite automaton, transitioning from state to state as it consumes input. | | | As demonstrated by this example, a pushdown automaton is more powerful than a finite automaton in that it can deal with arbitrarily nested constructs. | | | This deterministic automaton is the core of the declarator parser mechanism. |
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http://www.cs.berkeley.edu/~smcpeak/elkhound/sources/elsa/doc/declarator.html
(1255 words)
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| | 5. Pushdown Automata and Context Free Languages |
| | 5.1 indicates, a pushdown automaton consists of three components: 1) an input tape, 2) a control unit and 3) a stack structure. | | | A (non-deterministic) finite state pushdown automaton (abbreviated PDA or, when the context is clear, an automaton) is a 7-tuple | | | over the alphabet X and hence of the language accepted by a pushdown automaton. |
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http://homepages.fh-regensburg.de/~zar39030/in/node6.html
(3250 words)
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| | exam2topics.txt |
| | Automata to Grammars You should know that a grammar can be found for the language of any pushdown automaton, but I won't ask you to find such a grammar on the test. | | | Know that not all context-free languages can be recognized by a deterministic pushdown automaton. | | | Deterministic Pushdown Automata Construct deterministic pushdown automata to recognize the language of given grammars. |
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http://www.mscs.mu.edu/~mikes/157/exam2topics.txt
(222 words)
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| | cfg.html |
| | Any string of this language can be tested for the membership for the language by a finite automaton if there is a memory such as a pushdown stack that can store a's of a given input string. | | | This pushdown automaton accepts the language { wcw | | | Let us consider the pushdown automaton < Q,, q |
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http://www.cs.odu.edu/~toida/nerzic/390teched/cfl/cfg.html
(1510 words)
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