Instantaneous description - recognizable language, Theory of Computation

Assignment Help:

De?nition (Instantaneous Description) (for both DFAs and NFAs)

An instantaneous description of A = (Q,Σ, δ, q0, F), either a DFA or an NFA, is a pair hq,wi ∈ Q×Σ*, where q the current state and w is the portion of the input under and to the right of the read head.

The directly computes relation is also the same.

De?nition (Directly Computes Relation) (for both DFAs and NFAs without ε-transitions).

210_recognizable language.png

 

Note that while this is de?ned identically for both DFAs and NFAs, in the case of NFAs it is no longer even partial functional; an ID may well have many successors. Moreover, it is no longer true that the only IDs without successors are those in which w = ε. The effect of this is that the transition function (δ(q, σ)) as we de?ned it earlier is no longer total or even functional: there may be some q and σ for which δ(q, σ) is not de?ned (in notation: δ(q, σ)↑) and there may be some q and σ for which there are multiple states which could be the value of δ(q, σ). We can accommodate both of these possibilities by taking the transition function for NFAs to be a function returning a set of states.


Related Discussions:- Instantaneous description - recognizable language

First model of computation, Computer has a single unbounded precision count...

Computer has a single unbounded precision counter which you can only increment, decrement and test for zero. (You may assume that it is initially zero or you may include an explici

Construct a regular expression, Given any NFA A, we will construct a regula...

Given any NFA A, we will construct a regular expression denoting L(A) by means of an expression graph, a generalization of NFA transition graphs in which the edges are labeled with

Possibility of recognizing the palindrome language, Computer has a single F...

Computer has a single FIFO queue of ?xed precision unsigned integers with the length of the queue unbounded. You can use access methods similar to those in the third model. In this

Xx, Ask queyystion #Minimum 100 words accepted#

Ask queyystion #Minimum 100 words accepted#

Design and implementation of the state machine, You are required to design ...

You are required to design a system that controls the speed of a fan's rotation. The speed at which the fan rotates is determined by the ambient temperature, i.e. as the temperatur

Designing finite automata, a finite automata accepting strings over {a,b} e...

a finite automata accepting strings over {a,b} ending in abbbba

Emptiness problem, The Emptiness Problem is the problem of deciding if a gi...

The Emptiness Problem is the problem of deciding if a given regular language is empty (= ∅). Theorem 4 (Emptiness) The Emptiness Problem for Regular Languages is decidable. P

Automaton for finite languages, We can then specify any language in the cla...

We can then specify any language in the class of languages by specifying a particular automaton in the class of automata. We do that by specifying values for the parameters of the

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd