Simple matrix languages

Simple Matrix Languages

It is shown that £t(1)[~(l)] coincides with the class of context-free languages [regular sets] and that ~9' is a proper subset of the family of languages accepted by deterministic linear bounded automata, It is proved that ~(n)[~(n)] forms a hierarchy of classes of languages in ~9°[~]. The closure properties and decision problems associated with ,9°(n), ,.9", ,~(n), and ~ are thoroughly investi...

A Homomorphic Representation of Simple Matrix Languages

In this paper we continue the investigation of simple matrix languages introduced by Ibarra (1970) as a subfamily of matrix languages. Simple matrix languages have many properties similar to those of context-free languages. In the following, we prove that every simple matrix language can be written as a homomorphic image of the intersection of the Dyck context-free language and an equal matrix ...

Efficient Learning of Some Linear Simple Matrix Languages

Simple Chain Grammars and Languages

A subclass of the LR(O)-grammars, the class of simple chain grammars is introduced. Although there exist simpio chain grammars which are not LL(k) for any k > 0, this new class of grammars is very closely related to the LL(1) and simple LL(1) grammars. In fact it can be shown that every simple chain grammar has an equivalent simple LL(1) grammar. Cover properties for simple chain grammars are i...

Simple-Regular Expressions and Languages

We define simple-regular expressions and languages. Simple-regular languages provide a necessary condition for a language to be outfix-free. We design algorithms that compute simple-regular languages from finite-state automata. Furthermore, we investigate the complexity blowup from a given finite-state automaton to its simple-regular language automaton and show that there is an exponential blow...